Ok I removed the block, FP, safety lock, and springs and cleaned them with brake cleaner. Didn't touch the extractor. Put the block back in dry, and greased the rest of the gun.
Symptoms remain. It will fire 2-4 then the hammer drops and no bang. Trigger has not reset which makes sense since the slide has not cycled, I guess. Primer shows no imprint at all......not even a suggestion of one. My guess is the safety lock is not getting depressed (upward), but when cycling the lower by itself I see no problem, lots of upward movement and no sideways wiggle. I will fool with it some more but I wish this $300 gun didn't have to go back to Sig for a $150 tuneup.