since i'm refreshing my bottom end, I figure it'd be nice to refresh the top while i'm at it, maybe take the casting lines out of the ports too.
my question is mostly with valve lapping. I don't want to have to pay for everything being reground, so I figured I could just do a quick lap on the valves and it'd be better than it is now. It's undoubtedly a good head, and doesn't need anything, but would I be doing it more damage to lap the valves than to just leave it as is?
If the valves are not leaking then leave them alone. You will gain nothing by lapping. They might even leak when you are done lapping! If they are leaking then it is probably time to replace guides which means a seat resurfacing (grinding) is in order.