I have a 4-speed trans from a 69GTS but I don't know for sure does any one have the codes?

courtnb@novachem.com

I would bet that it is the 2.66 1st - 1 to 1 4th "close ratio" 833 4-speed.

Get it up on the bench, mark the input shaft and the output shaft and count the turns.
(it helps to slide-in a rear U-joint yoke on the 66 & up units)

Select first gear, (rear shift lever forward) and turn the rear yoke exactly one turn, the front input shaft should turn 2.66 times. (just over 2 1/2 turns)

Here is a handy tip, 3.09 first "wide ratio" 833 have a small ring machined into the input shaft, just before the clutch disc splines, this makes it easy to spot them with-out counting a bunch of turns.

Here is a ratio reference chart:
DD