I was looking at he AX-5 tonight.....
I really do not think there is a different shaft for the 2WD and the 4WD's. Reson being my 4WD tranny has the groves (for the clips) and place for the 2WD tranny spedo gear. I may have to get one and split it open just for the fun of it! LOL! As for resell, you are really limited b/c the traany used most IMHO is the 4WD one. But that last part is just my opinion.
By the way, Where are you?