THREAD SIZE NEEDED

So if I chase the nut and the shaft (bushing end), would a little blue loctite on the threads suffice...Or does it matter? Chasing would defeat the interference fit would it not?
yeah, you'd probably be fine. maybe get crazy and throw a little red on there if you're feeling saucy.

chasing the shaft (giggles) won't matter, but cutting new threads on the nut will. you could also peen the nut after chasing it.