.045-.050 is where I run them with msd box.
Try stock heat range and get the timing right 'if it pings now'.
I havent read the entire thread.
I just see fouled plugs that shine like they're eating oil...and 185-190 cranking that should eat 'min 91 octane' pump gas okay.
Seals making it run bad...if they cause fouling , yes .