which heads are best suited

My 65 Barracuda has an older crate 360 with 2.02 heads and pistons are .040 in the hole. My ? is I have a set of 1.88 heads milled .080 that came off a 273, and i am considering them to boost my CR. Would I really be gaining any benefit of the milled 1.88 heads over the 2.02 and do you think I will have valve to piston clearance problems with a .510 lift cam. The pistons are flat top with some valve clearance already cut in them and I do not know the current CR. I am guessing between 9-10 and what increase of CR might I expect with the milled heads and can I still run pump gas? Thanks everyone!!!