The 8 1/4 thread

I think if you recheck the ring gear, it'll be 45 tooth, = 3:21 ratio, and it will fit the 2:76 and up carrier ..

And to the best of my knowledge there was no offset housings, only different gear/suregrip carriers to compensate for the vast pinion gear diameter size changes thru the ratios.

A 5:88 gearset may have a pinion gear diameter of a coupla inches, while a 2:76 ratio pinion gear diameter may be over 3 1/2 inches ish.. gotta move that ringgear over to the pinion somehow, thus different carrier. lol