Correct.
Method #1 - swap out the "internal" slave setup for the "external" slave setup. Take the old "internal" and give it a thorough overhaul as a spare, put it under your bench for when you need it. If/when you do the swap, move the bellhousing (and related parts) and front bearing retainer over from the "external" setup, and you're done.
Method #2 - Do the latter half of the above swap.
But, since you've got to pull the transmission out anyhow, might as well just overhaul the thing before you put it in. As noted, you will need to swap hydraulics as well.
I'll be doing this swap (88 going from BA-10 to iAX-15 to eAX-15, kinda roundabout...) and I'm actually looking to do aftermarket hydraulics - I think I have the part numbers around here somewhere. Call me cranky, but I don't trust "prefilled & prebled" hydraulics, especially where a hygroscopic fluid is used. I change my clutch fluid just as often as my brake fluid - every two years. It's easy enough that it isn't worth not doing, y'know?