"...those gaskets were much thinner than the gaskets normally made available today."

Yes, they are thin and do not affect the bolt hole or port alignment.

Mopar Mitch "Road racers and autocrossers go in deeper and come out harder!"... and rain never stops us from having fun with our cars... in fact, it makes us better drivers! Check out MOPAR ACTION MAGAZINE, August 2006 issue for feature article and specs on my autocross T/A!