I don't know whether he tied in his RWAL system but I should have my 4WAL system working in my truck. Its only link to the PCM is the VSS signal. It's a 128,000 pulse per mile signal that comes off the PCM. My 95's abs unit works with a 2002 PCM ABS VSS output right out of the box (in theory).
EDIT: By the way, GREAT looking swap. I cringe when I see wires flying everywhere, greasy parts, etc. on people's engine swaps. Yours looks like it came that way from the factory. That's what I'm going for as well, but didn't have the luxury of a donor truck. Nice work!