I've only been doing mopars for 48 years. But for a small block I prefer Badger pistons along with the SCAT I beam rods. With iron heads it's not a good idea to go over 10:0:1 compression because of pinging witch will kill an engine.
302's shaved 50 with a steel shim gasket and a 9:5:1 piston will give you a CR of 10:0:1. You also need to bore that 318, 60 other wise you don't have enough bore to create the velocity needed with the big ports to create thge cylinder pressure needed. Getting 400 horse out of a 318 is very easy to do. A 750 holly or edlebrock card on a performer intake works real good. Also Summit headers are private label headers made by hooker for half the money.