sort of. the '79 uses a 3-speed BW55. Starting in '81, the 4-speed AW70 cam in, but the BW55 continued in a few cars until early in the '82 production run.

The simplest would be replacing the BW55 with another.

You *could* do an AW70. Of course you'll need the driveshaft from the donor car, and to do some wiring for the overdrive - but here's the problem:

The AW70 is longer than the BW55. 81+ cars have holes in the frame rails to mount the crossmember further back. '79's don't have the holes in the rearward position. You'll need to fabricate.

or find a rusty donor and convert the car to stickshift.