1964 Dart Owner - In Over My Head

Both of My '64 GT's came w/2.93's, one local(225 PB auto Cp), and one from OK(225 column 3spd. 'Vert). I'd look at the build tag codes on the fender, and the sheet under
back seat bottom to confirm the axle OE build. You have the original window sticker from the '66 I'm guessing? Really sharp ride You've got there BTW!!