why do you need the shafts on the front?
you need them to hold the oil in the diff in place
so you remove the shafts, drain the oil, job done
why do you need to pull the stub axles out to pul the shafts out? it's just a circlip (a quick search of front driveshafts should pull up the question posed only the other day about someone (i think it was ian maic) who's posted up pics about them
if you faff about with the front hubs you need to change the brakes because the offsets are differnt, you need to change the struts because they are thinker on the 4wd cars, you need to change the tca,s because they are different, you need to change the arb because thats differnt, then you have the crossmember, steering rack, steering shaft, etc ,etc

so, you still want to go through all of that and STILL have to source a 2.9 sump and crossmember etc?