The local folks are quite different from what you describe, and from what they said travel a great distance to periodically attend an SSPX Mass rather than going to Mass at any of the local Catholic Churches. Could you point me to someplace where the SSPX officially distances itself from those who do not accept all the dogmatic teaching of the Church and explains that they do accept all the dogma of The Church?
I didn't see it on the sites I've checked out so far but maybe I missed it because I was reading what they claim justifies their original split.
Regards
Odd, you talk about “SSPX folks”. There are ordained priests, a few lay brothers and sisters and that group is the SSPX.
If laity espouses sedevacantism, they are schismatic in their belief, but they are not SSPX and the SSPX has denounced that belief here: http://www.sspx.org/sspx_faqs/q15_sedevacantists.htm
“Ummm, I found a few SSPX folks locally to talk with (by accident, really) and not only do they not accept the Pope as sovereign and insist there hasn’t been a legitimate Pope for quite some time.”
It doesn’t matter what your imagined “folks” think; the SSPX has just proclaimed the supreme government of the Church belongs only to the Pope in his monarchial position.