Yupp the torque converter goes in with two clunks. Mitsubishi ATF is said to be only what to use in them. Based on a few conversations I've come across online. Cheapest place I found to get SPIII was $8/quart+shipping.
I'll be using the Mitsu SPIII in the trans and Redline MT-85 in the transfer case.

What seals and gaskets are you changing?
I'll be doing a swap of trans, transfer case, and rear end in the coming weeks too.
Something I noticed and didn't expect when splitting a spare trans and transfer case was a guide pin below the transfer case shifter, thought it was a broken bolt at first.