VR6 turbo swap it instead.
Or use a AAZ, or a 1.6 diesel with a turbo if you want to keep it simple.
A TDI-M if you want to spend a lot of money.
All the TDIs will require a big jump into the electrical. Talk to Josh @ Yoshifab, as they've already done the TDI into a Volvo swap.
I have talked to Josh, and he sort of told me to just buy some guy's kit and use a Toyota truck transmission. I'm not really impressed by the idea, and like the concept of making use of as much VW/Volvo stuff as I can. It also sounds cooler to say it still has a Volvo BH.
For the pure sake of the discussion:
The D24/D24T, from behind, "looks" like the VW 1.6IDI used in the mk1/mk2/b1 cars. The 1.6IDI has the same flywheel bolt pattern and bell housing pattern as an ABA, TDI, 8v, 16v, etc. The VR6 is a different animal as it uses both a different flywheel and bell housing patterns.
What I plan to do:
240 D24 m46 bell housing milled out to accept Kaplhenke T5 adapter
4cyl mustang T5 trans (1-1/6" 10 spline input shaft)
AHU/ALH/1Z 1.9L TDI engine (have a lead on two good running AHU's with harnesses and ECU's)
G60 flywheel (single mass, not prone to exploding like the stock AHU dual-mass)
VR6 pressure plate and custom sprung center VR6 clutch disk (stock clutch material and diameter, splined for Ford T5)
The VR6 OEM clutch is rated for somewhere between 250 and 300 Ft/lbs depending on who you ask. I plan to run a Malone Stage 2 tune, which will put me at the ~220 WTQ and well under the max for the clutch. I have to fab my own mounts and determine the best way to mount the starter (not sure if I'll use a D24 unit or the TDI unit mounted with the gear pointed towards the rear of the car).