I wouldn't use the shafts off a 2.0 8v on a 3.2 used for towing.
There isn't a huge difference between the torque figures of the petrol 2.2 and the 2.5/2.6 so, for the purpose of the exercise, they will be fine.
If they're from the 2.2 diesel, that has as much torque as the 3.2 so, again, not an issue.
The rear half of the propshaft is interchangeable as well, but the front half varies according to engine AND gearbox types.
The different part numbers for the various engines will be due to the possibility of different shaft diameters, but will also vary if you're talking just the shaft or the entire assembly with CVs.
As for the different part manufacturers, then you can reasonably expect different part numbers from each supplier.
It used to be possible to buy CV boot kits for the inner and outer CVs, (they're different), and from memory, you pull the drives haft, break down the outer CV/boot to service the inner one first and then service the outer.
It’s possible that the boot kit you have is the opposite end to the one required.