What would it take to convince you that someone claiming to be the pope is not the pope? Is there any belief, statement or behavior of his that would convince you that he cannot be the pope? Or is the papal election itself sufficient to ensure that he is pope, irrespective of anything he might do or say? I'm just trying to understand your theory of the papacy.
Those are the perfect questions to ask any anti-SV. I guess they would have to put on lay clothes and leave the Vatican never to be seen or heard from again. But even that might not do it from what I have seen.
A while back, someone sent me a link to a topic on another forum (it is a SSPX forum in the sense that CathInfo is a Resistance forum, that I am not a member of) in which this very question was asked of the membership. I don't have the link anymore, but the answers were interesting. In the end, the responses indicated that nothing ever could convince anyone of sedevacantism.
In fact, there was a poster by the screen name of Stubborn (I don't know if it is the same poster as our very own Stubborn) who candidly replied that nothing could possibly convince him.
The conclusion I drew (besides that I was not going to join that forum) was that anti-sedevacantism
is the only dogma that unites them. The more I see how anti-sedevacantists think, the more I see how similar it is to Protestantism.