Hello Runwld2! Yes i have had my fingers in theese heads a few times, when you disassembly the head remember to mark all lifters,valves and such, so they get put back in the same place they came from(especially the lifters because they get worn in together with the cams). It`s a good idea to re-grind the seats and valves when you all ready have the head off. I dont know how much mileage your car has, but why not change the valveguides as well?. About the leakage, check thorogly that the cyl.surface is dead straight, any questions about it? give it a minimum shave!. finally when you are assemblying the head DON`T FORGET THE O-RINGS AROUND THE SPARKPLUGS!!!. Trust me it`s easy to do and you don`t remember them until you are ready and are cleaning away the gasket boxes afterwards!!!
Be careful when adjusting the camtiming, if one of the cams is set wrong you`ll
have contact between valve/piston, and i don`t have to tell you that that gets very expensive. Take it easy and use correct manuals and tools and i`m sure you`ll get it right.

Hope i have helped you some.

DE. Sweden.