How much clearance? Running a 428 CJ with solid roller & FElony heads. Won't be going over 6500 and only on occasion. I've read somewhere 0.080 for intakes and 0.125 for exhausts. Good numbers?

I think I have a way to remember which way the pistons go in...

You mean the piston? Yep TDC.

Thanks all. Will check tonight. At work now... As for the clay method, I saw no point as the valves hit the pistons with heads in place with gaskets using check springs.

The heads are FElony. The tool used to find the valve centers is an old valve modified. See picture. Brent, I did exactly what you suggested. The arcs are what I got. Jay, I don't see how I could have made any errors. The "punch" was in the valve guide and the head bolted to the block. I will admit that just because I can't see an error doesn't mean one wasn't made. Assuming my method is correct, it looks like I have two options: BIGGER notches or different pistons. I do have the original iron CJ heads but you know how it is when you want mo'power.  This is the only thing holding up my engine build. This kind of machine work is beyond my ability at home. I suppose I could take the engine to a machinist but this looks like an involved/expensive task whit no assurance that such a big cut won't compromise the pistons.