PS: anyone know an EASY way to remove axles from the housing?
Easiest way is to use a slide hammer - if you don't have one, either use your brute strength or if it's a drum rear (unlikely in your case), you can attach the brake housing? hub the opposite way, screw it on and use it to yank the axle out. This is, of course, after having undone all the nuts attaching the axle to the diff housing.
I've done it before in scrap yards just using brute strength - good work for your muscles and adds to the list of scrapyard macho tales.
P.S. How do you know your axles are the earlier zenki ones? Is it possible they are kouki?
Or did you replace the axles from a stock AE86 diff? If so, remember that's an S series diff and not a T series diff ...