The big question is, the bushings o.d. is .307 too big for 1/4 32, so maybe 5/16 32, threads are usually smaller than actual size of .3125.
It is just a bushing, soft mild steel is all they were made of, no need for them to have any temper to them.
The firing pins should, and I believe the Grade 8 bolts will be fine.


David