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 SV's are in the same position as the schismatic Orthodox, now that 60 years have passed and it is clear they are entirely separate from Rome, neither accepting any Cardinal or Roman Clergy, nor desiring and making to haste to enter that communion as soon as reasonably possible; whether they are 61 year SV's, or schismatics and heretics who hold the See of Rome has been vacant for 1000 or 1500 year due to Christ allegedly failing in His Promise. SV's not only deny the dogmatic fact that a Pope recognized by a Catholic Hierarchy is infallibly the True Pope of the Roman Catholic Church, but also that communion with him is necessary for salvation.

This question is directed primarily to non-sedes, who know 61 year, or 150 year, or 1000 year SVism is all false doctrine, a heresy against the Church of Rome's Indefectibility, a falsehood that denies the Indefectibility of the Teaching Church and the Ordinary and Universal Magisterium of the Catholic Church, and heresy that denies the Vatican I Dogma on Perpetual Successors to St. Peter. 

It is Solemnly-Defined and Thrice-Holy Catholic Dogma that subjection to the Roman Pontiff and communion with the members of the Church subject to him is necessary for salvation. One cannot doubt a universally recognized Pope without committing mortal sin. Why do some non-SV's, then, insist SVs as SVs can be saved?

"Moreover, that every human creature is to be subject to the Roman pontiff, we declare, we state, we define, and we pronounce to be entirely of necessity for salvation (‘de necessitate salutis’)."
Pope Boniface VIII, Unam Sanctam, n. 9

"And since it arises from the necessity of salvation (‘de necessitate salutis’) that all the faithful of Christ are to be subject to the Roman Pontiff, just as we are taught by the testimony of the divine Scriptures and of the holy Fathers, and as is declared by the Constitution of Pope Boniface VIII of happy memory, which begins ‘Unam Sanctam,’ for the salvation of the souls of the same faithful, and by the supreme authority of the Roman pontiff and of this holy See, and by the unity and power of the Church, his spouse, the same Constitution, being approved by the sacred Council, we renew and approve."
Pope Leo X, Fifth Lateran Council, Session 11, 19 December 1516.

The Catechism of the Catholic Church defines these three sins against the faith in this way:

2089 Incredulity is the neglect of revealed truth or the willful refusal to assent to it. 
"Heresy is the obstinate post-baptismal denial of some truth which must be believed with divine and catholic faith, or it is likewise an obstinate doubt concerning the same; 
apostasy is the total repudiation of the Christian faith; 
schism is the refusal of submission to the Roman Pontiff or of communion with the members of the Church subject to him." [Code of Canon Law c.751]

https://www.ewtn.com/expert/answers/heresy_schism_apostasy.htm

Just like with Orthodox, no Catholic should say schismatic sedevacantists, who die in final impenitence as Sv's, can be saved. They can be saved, provided before their death, they retract their errors, and recognize the Pope and the Bishops of the world in his communion.

"it suffices Us to be able to state that a commemoration of the supreme pontiff and prayers offered for him during the sacrifice of the Mass is considered, and really is, an affirmative indication which recognizes him as the head of the Church, the vicar of Christ, and the successor of blessed Peter, and is the profession of a mind and will which firmly espouses Catholic unity. This was rightly noticed by Christianus Lupus in his work on the Councils: “This commemoration is the chief and most glorious form of communion” (tome 4, p. 422, Brussels edition). This view is not merely approved by the authority of Ivo of Flaviniaca who writes: “Whosoever does not pronounce the name of the Apostolic one in the canon for whatever reason should realize that he is separated from the communion of the whole world” (Chronicle, p. 228); or by the authority of the famous Alcuin: “It is generally agreed that those who do not for any reason recall the memory of the Apostolic pontiff in the course of the sacred mysteries according to custom are, as the blessed Pelagius teaches, separated from the communion of the entire world” (de Divinis Officiis, bk. 1, chap. 12)."

Notice: if the world recognizes the Pope, you must do so also, otherwise you are separated from the communion of the entire world.

See: https://catholicism.org/sedevacantism-and-schism.html it is necessary for this Truth to be proclaimed openly and frankly, so that sedevacantists of good will may retract their errors, humbly re-enter the Church through the Sacrament of Confession, and be saved.

In the same way as it must be proclaimed to Protestants and Orthodox, and Jews and pagans, it also applies to SVs and Old Catholics. Anyone who reasonably reflects on all this will see that Bp. Fellay is right in doing what H.E. is doing, and SSPX and Indult Traditionalists are right in retaining communion with Rome.

No disciple of Father Feeney could become a sedevacantist. Why? I will let Father Feeney answer that question with this passage from his Bread of Life:
"The gate of the Kingdom of Heaven in beatitude was opened for the first time by the entrance of Jesus. The keys to that gate were put in the hands of Christ’s Vicar on earth when He said to Peter, and his successors: “And I will give to thee the keys of the Kingdom of Heaven.” No matter what we do in the way of justification, we can never enter salvation unless we enter it under the leadership of him who has the keys to that Kingdom.
That flesh and blood Vicar of Jesus Christ is none other than the Pope, our Holy Father, a visible head for Christ’s visible Church. He is a man whom we can point to as the visible Vicar on earth of the visible Christ in eternity. He is as pointable-at now in time as Jesus once was when He walked the streets of Jerusalem, followed by Peter and His Apostles.
It is a defined dogma of the Catholic Church that no one can be saved who is not subject to that flesh and blood Vicar of Jesus, the Roman Pontiff. It is one of the requirements for salvation. Justification is useless for purposes of the Beatific Vision unless submission to Christ’s Vicar has been added to it in essential complement.
Pope Boniface VIII, in 1302, infallibly declared in his bull, Unam Sanctam: “We declare, say, define and pronounce, that it is wholly necessary for the salvation of every human creature to be subject to the Roman Pontiff.” A defined dogma can never be changed. It holds for every age; it applies to every generation, until the end of time.
If you do not have a belief in, and submission to, a visible Holy Father and a visible Church, with clear distinguishable marks, you will never get into Heaven."

Jesus is not my name, so I think it is wise to not make the kind of judgement about an issue which is so strongly held and debated by clergy beyond my paygrade. It is the height of folly for someone to ask who seems new to tradition especially in such a confrontational way, especially since you seem to not grasp all the concepts involved

Both sedeism and R&R strive to remain faithful, for R&R, that means remaining faithful even if doing so means going against the wishes and teachings of the conciliar popes.

But striving to remain faithful is about the only similarity between the two camps. As it is, R&R leaves it at striving to keep the faith. If sedes could get themselves to leave it that, then this unedifying disunity between the two camps would not exist, or at least have no reason to exist any longer.  

As it is, for whatever reason, because the sedes are not content to leave it at that, it only adds to the disunity among traditional Catholics. There is no reason for sedesim, none whatsoever. To declare there is no pope while one occupies the chair, can be and often is, an act of iniquity and source of scandal because the Church has always taught that to do so *for any reason*, is an act of schism.  

R&R only opine the obvious regarding sedesim, i.e. we realize the popes' subjects have no need whatsoever too, nor can they  ever determine the status of the pope - nor is there any need to - especially considering we can do absolutely nothing about it.

The sedes feel some interior motivation, or pressing, sometimes obsessive need to decide the popes' status - apparently not realizing that if we need to or even could decide such a thing as that, it would most assuredly have already been an official teaching of the Church, but Holy Mother knows better. She knows that if such a thing were left up to anyone but Our Lord, it would have most assuredly been used against probably every single pope, holy or not, since St. Peter. It's not our business, we have no right and we have absolutely no reason whatsoever to decide the status of popes, because to do so is risking schism.

As +ABL said:
"We do not follow the pope, but he is the pope. He is the pope. . .but we do not follow him when we know he poses a danger to the Faith. That is the principle...."