Valve to piston clearance

You're not in over your head, but here are somethings to consider. You say you're hitting the exhaust valve NOW. Ok, so as Roy pointed out, .100 on the exhaust and .080 on the intake is the norm minimum. So, if you're hitting on the exhaust now, you're obviously going to need MORE than the .100 minimum. So yeah you see you're out of gasket territory as far as being able to fix that. How much is anybody's guess. First thing "I" would do is pull it down and find out how thick the piston tops are in the area of the valve reliefs.

There's no sense in finding that info out first without a tear down, because that's what you gotta do to fix it. So get busy with that.

Man like Roy said, that's a LOTTA cam! lol

I'm not sure I wouldn't prep another block. It's always an option. That mess would always be in the back of my mind.......no offense.