Sounds like you need to look for a new head. .080 is way too much. You will never gain it back with a HG. Reminds me of a funny story. My buddy has a 70something Japanese Fairlady with an L28. He blew his HG, and I helped him fix it. We take the head off, and it's badly warped. I tell him to take it to a machine shop to get it fixed (needed to be straightened, then shaved). So a few days later he has the head back. I take a look at it, and first thing I notice is the shiny surface. Very smooth. Nice. Then something grabs my attention. The number 1 and 6 chambers are FOOTBALL SHAPED! 2 and 5 aren't much better. This moron machinist just shaved the head and called it quits. Didn't even notice that he shaved them beyond the chamber edges. Royally ruined that head. You wonder how some people stay in business.