Sure if the combined block and head deck are not off by more then .005". Unless your chasing down every 1/8 of a point of compression then use aFel Pro print-O-seal gasket.
A long time ago we used fel-pro's blue gaskets. Also a stock motor. Did not notice any difference over the steel ones. I thought the nos steel ones are .020 thick instead of .015
I like to use the NOS 430 gaskets partly because they are .020, and also the bore size on the blue fel pros is huge while the original gaskets are sized for the smaller 430 bore, and actually won't work with a 455.
I I never heard of .015", I have some .020". Doesn't mean they don't exist I just never heard of them. You'd gain .1 in compression ratio with a .015 0ver .020. I'd stay with .020 with flat surfaces.
Understood. It's just that i can get an nos set which is steel and .015" so better find a .020" set and use that one when needed?