3spd trans questions...?

[bad6772]

hey guys couple quick questions....my truck is a 67 lwb with a 250/3peed.and the tranny is going out....2nd gear mostly. and i came into two 3speed trannys.....one tranny is of a vehicle unknown...and one is i was told is out of a 67/68 chervrolet truck, both of these trannys look exactly the same.....in every way....both measure 21 inches...however both are nothing like what i have....? my tranny is small 17 inches and very compact...i have been told by a few people that the trannys i baught are for my truck and what came in my truck..lol but they are not for MY truck...is my small tranny rare, left over from 66s or ???? my trans bolts up to the bellhousing a little differnent( as there are two bolts on the inside and two bolts on the outside...meaning i would have to remover the inpection cover to access two bolts......? im thinking i could make one of the trannys i baught work...with just a simple drive shaft mod...also i do not have a rear tranny crossmember in my 67? but both the trannys i baught have the mounting points on them and mine does not.....any help or a sence of direction would help....tony