Be sure that you really study both sides of the block and compare it to the head gaskets when you get them in. When doing my project, I had a couple of sets that were listed for the engine, along with a few other minor variations. What I found was they fit the studs perfectly but some passages were obstructed. They could have been modified to fit using a dremil tool with a small cutting disc but I was fortunate to pick up a pair of solid copper head gaskets that were an exact match prior to final assembly of my engine. Not sure if the copper gaskets are really any better but they were a high performance item from the early 50s and I figured they would be more understanding and forgiving of my heavy handed work methods. Having three sizes of hammers for auto repairs works well for most things but the engine seems to be more sensitive.
