Help on 408 build
My suggestion(to be added to what I’m sure will be many) is, pistons and a little bigger cam.
You can sell the ones you have to help with the cost of new parts.
If you wanted to stick with the Lunati cams, just get the next bigger one.
It’s a better size for your combo really.
The heads may not have been milled that much.
Most aftermarket valves have less of a tulip shape than the OE valves, and will reduce the chamber volume.