i need a little 340 help. Lets Talk head gaskets

It definitely wouldn’t hurt it to go through a thorough disassembly and cleaning that would be part of all that.
It’s a balanced assembly. I had a shop check it. They also checked the block before punching it out to fit the .040 pistons. Yes, it looks worse in the pic than it is. Mostly discoloration. It’s clean and true. This was a promise to my dad kind of a tribute. The parts are matched. I just wanted to use the aluminum heads.
Normally I would just stroke kit and use new parts.