I did a TFI on my '88 Wagoneer, too. Didn't publish it yet on 4x4Wire, but it's on my personal site here.

I'd assume the newer Ford parts would be easier to find than the older Jeep/Ford parts. The trick (for me) was to put a decal inside the engine compartment with the details, listing parts and donor vehicle ('84 F350 w/460). I think the replacement parts were cheaper. Well, not the wires.