Wow, I really like this build! you are keeping it clean and classy and I really respect that. In terms of the head, it's kinda a crap shoot but there are different thicknesses of gaskets on different engines. The other thing is, and this will REALLY help your performance, you should see if the piston is coming up really high in the exhaust port even when it is at its LOWEST point. This is not good for exhaust flow and if you make a spacer to put at the base of the cylinder you will correct the flow and simultaneously lower compression. In terms of your stripped stud hole, well, I've been there, and you really can't get away with loctite to hold a stud in a stripped hole. You can try JB weld but I've never had luck, the only thing I would use in that specific location is a helicoil, if you're gonna do it, do it right. And as for the pipe, enjoy it! it's an awesome pipe!