318 build

I am building a semi-budget 318. I just bought a set of speed-pro .30 over forged pistons on ebay for 200$. I have a 68 318 motor that I hope has a forged crank in it. I think I'm going to use a set of 73 318 rods with pioneer rod bolts and have it balanced. I'm using magnum heads. I have two sets of sealed power .30 over rings(e178x30) that I might use but I am planing on using nitrous. I figured I would need file fit rings. I'm wondering if I will have enough piston to valve clearance to use a .500ish lift cam? I am not decking the block. I bought a a-833 for 200$ and it came with a flywheel. I'm not sure how to tell if its a forged or cast crank flywheel. This is going in a 1976 Plymouth Scamp.