[Mike Kelly]

Bad luck with that buggered block thread. The block threads are somewhat delicate and can be damaged/stressed during the process of removing the old studs , particularly if there's any crud or corrosion on the end of the old studs.

The repro head studs available are often low quality .The studs I bought are a loose fit in my GPW block. I am thinking maybe I can machine up some new studs . The experts reckon it's best to tighten the block studs only finger tight and use permatex sealant on the threads.