Let me add this pic of the head.
Measured the bad piston last night and found it .012 under. The #6 bore is matching the rest a 3.915. Seems that piston got hot and shrunk when it cooled.
What are you seeing in the pics that is wrong? My machinist/auto buddy came by last night and didn't see anything wrong on the head, gasket or block that would indicate a problem.
Thanks for taking the time to reply everyone.
