Let's see if this helps. See pic.
The gear drive transfer case is composed of two sections. The front section is the high/low range box. Behind it is the section that lets you shift between rear drive, and 4WD. You take a donor transfer case, take it a part to end up with just the high/low box. So looking at the pic ...
- The low-range box is off a donor transfer case (it has the shifter). It's bolted to the transmission.
- There is an adapter between the low-range box, and the transfer case. Essentially, you are going to bolt two low-range sections together using the adapter.
- Bolted to the adapter is another gear drive transfer case.
If you look close in my pic my transmission (R151F) was originally a forward shift and I converted the low-range box to a top shift. The block off plate I made for the transmission is (sort of) visible right behind the tranny shifter.
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