The donor engine is an AHU (98 Jetta standard transmission) . recipient is a T3/Vanagon factory 1.6 Diesel, standard 5 speed.
I believe these are my clutch options:
1.6 flywheel and stock T3 diesel clutch. This is a really bad idea as the TDI will slip it.
AHU flywheel and PP with stock T3 gasser clutch disk. This will work, parts may be hard to find.
AHU flywheel and complete clutch. Transmission input shaft on transmission changed to match disk splines. This will work, uses current parts and kits.
ALH dual mass flywheel and complete clutch. transmission input shaft changed to match disk splines. This will work, uses current parts. Dual mass flywheel have higher fail rates.
Bear in mind that this is for a heavy T3 camper, not a race car :-) The AHU will be at stock or close to stock output.
Opinions please!
Your info is correct. I would add that the Vanagon trans is known to be somewhat weak especially when pushed by an engine with significantly more torque than stock. The diesel power pulses are also fairly sharp (as compared to gasser engines). That combo of higher torque and stronger power pulses is hard on the trans. While the dual-mass flywheel has a higher failure rate than the single-mass flywheel it is also supposedly nicer to the trans by evening out the power pulses. The dual-mass flywheel is less expensive and more readily available than the trans.
I can't venture an opinion being way too inexperienced.
However will be monitoring this thread / topic as I'm on the verge of making the same swap.
Except that my rig (91 Syncro Doka) has a 1.6 TD (JX).