C-4 Swap Question

[65 coupe]

I have a '65 with a 200 and a 2.77 3-speed manual. I plan on swapping the manual out for a C-4, which I already have. I was wondering if anybody has done this before, and what the swap would require.

The donor C-4 I am using is coming from a whole 200 engine/tranny assembly, so I have the starter, lines, radiator, linkage, ect...
The biggest question I have is about the driveshaft. I know the auto accepts a different slip yoke, but can I reuse my driveshaft? Someone told me I might need a pinion yoke from the rear end of an auto car. Are the pinion yokes different lengths?
I haven't had a chance to do any measuring, since the car is at home and I am at college, but I really just want an idea of what I am going to need to do.

I was thinking about just going ahead and getting a new driveshaft made at a local shop, since I would need a new slip yoke, pinion yoke, and the u-joints are shot anyway. Is this worth it?
any suggestions?