make sure the nuts and studs are the same; metric/SAE
you say the nuts are stripped, probably the stud/bolt is messed up also.
get a DIE and clean up the threads, and make sure no chips/junk fall into cylinder
if you pull the head. Sometimes a few flat washers will get you pass the bad threads, and when the engine warms up, snug up the head bolts with a staggered pattern.
DO NOT over tighten.
I think you can reuse head gaskets but NOT go without them. You need a good seal for compression and ignition and changing/altering head gaskets that small does'nt matter.
You can get a few more mph by leaning forward and slapping your ass and hollering yippee ky oooooo
good luck and happy trails to ya. jimmiegimme