On an '89 Bronco II at least, the dummy T-case was a fully machined BW-1350 case. Even had the tag on it stating that. It had the fill and drain plugs (even though it was empty of fluid) and a freeze-plug type punch-out where the front output would be. The shaft it used appeared to be the same as what would be found in a functional t-case, minus the sprocket(s) for the chain. And it had a couple clips to keep the two pieces of the shaft together with a sort of gear looking sleeve (which I'm guessing is how a functional t-case goes into and out of neutral). It's also missing the planetary gear on the front plate.
I think I have some pictures around here somewhere of it, I'll have to look. If I can't find them I can see about getting some more, I have a complete one minus the front plate since I took it off my choptop when I did a 4x4 conversion. I stole the front plate from it for a manual BW-1350 that the front plate had a couple cracks.
