Raoul,
For the sake of your soul you should get conditionally reconfirmed by an unquestionably valid Catholic Bishop.
http://www.sspx.org/Catholic_FAQs/catholic_faqs__canonical.htm#thuclineAre the Masses of Thuc-line priests valid, and can we attend them?I do not believe that there is a strong reason to doubt the validity of the episcopal consecrations performed by the exiled Vietnamese Archbishop Ngo Dinh Thuc. However, there are several lesser reasons, that might be considered sufficient to establish some kind of positive doubt in the matter. These include the absence of correct witnesses during the original ceremony of consecration, which was done in private, and in the middle of the night.
Also relevant is Thuc’s confused mental state, as evidenced by his public concelebration of the New Mass with the local Novus Ordo bishop of the diocese of Toulon, just one month before these consecrations in 1981. Also, the lack of conviction can be seen in the fact that twice he consecrated bishops illicitly and twice he requested absolution from the canonical punishment of excommunication. These frequent changes indicate that he was a man who, to say the least, lacked conviction about what he was doing. This is further confirmed by his failure to join the Coetus internationalis patrum, the traditional group of bishops at Vatican II, and by a certain liberal tendency that he showed during the Council, speaking out against discrimination directed towards women and in favor of ecuмenism.. Consequently, although the logical thing would be to presume that he did have the intention of confecting the sacrament of Holy Orders, the absence of co-consecrators, and of a clear purpose, does open the door to some astonishment and doubt. Any doubt concerning the first bishops that he consecrated would clearly be passed on to any other bishops and priests ordained as a consequence.
The moral theologians say that we must hold to the pars tutior, or safer position, when it concerns the sacraments. Consequently, in case of doubt, it would not be permissible to go to these priests for the sacraments, unless there was no other priest available, and in danger of death.