early 4 spd trans.

Yes
But
The early trannys(65down) have a ball and trunion hook-up to the driveshaft, sortof like a modern CV shaft. To change it to a slip yoke style, you will need the 66up parts namely;a mainshaft, a rear extension housing and the slip yoke driveshaft. Additionally the later parts have a larger diameter speedo gear set up.
Some guys say they put a pretty good amount of power through that old-style coupler.IDK. I hooked a 340 up to one once. It held up for over a year,and was still in there when I sold the car.I have blown several 7260 joints with a mild 360(425hp)
The early units also have the 3.09 low, as compared to the later 2.66low. That 3.09 works very well with 3.55s and even with 3.23s. My stout 360 doesn't notice the wide 1-2 shift.I like it a lot. The 3.09 has 16% more giddy-up, but when you hit second,your engine better be able to pull it; so 3.55s are still the gear of choice in a streeter,especially with a short stroke sbm.My 360 with a 230* cam pulls 3.23s OK.The 223*cam was better tho.That cam pulled anything!