Wow, it looks like my idea to apologize ahead of time works! That's great!

Michael,

I expect that the pistons are not hurt by the valve contact. That is not to say that they are not in need of replacement due to wear. Micing the cylinders will tell that story. If you can't catch a ridge with your fingernail, I expect cylinders, pistons and rings are probably okay.

Have you been able to examine ALL of the timing chain associated components such as the guide rails and such? You will be able to get the head back in shape relatively easily. It obviously will take 6 exhaust valves and you should have them replace the valve guides at the same time. Be careful not to drop any of the tiny "cups" that fit between the rockers and valve stems.

Good luck with your further exploratory surgery.

Have a great day,