Help with decking or not?

what aj and nm said above
you have checked the deck with the engine mocked up not just a paper calculation?
"So you never know 'til you measure." I mentioned odd block deck angles above
so measure all four end holes
if .51 I'd sure use the .028 gasket as aj said you are on the downhill side of quench
sure- tell us about chassis, gears, convertr, intake, exhaust etc and most of all usage and you will get more cam suggestions which can be sorted out for what you need
or just pick the bottom cam from the catalog page- like that works