lazy_stang

Hey guys, I am looking at ordering some "budget" heads in the next week or two. Anyways Im not sure what to go with in term of valve size. If I go with 2.02" intake valve I read that I will have Piston to Valve clearance issues. A tech from Patriot said that I can run there heads on a stock short block without problems. How do I check piston to valve clearance. I dont want to end up ordering heads and then find out after that I cant run them with my current setup and have to buy new pistons...
currently I have .020 over forged ford pistons, and an E cam. some other stuff too but its over top of the heads