There is no such thing as a specific crossmember for each t-case. They are separated by the years.
Up to '84 are all "flat" crossmembers like the pictures show. But the '81 to '84 crossmembers are flat and look a little different than the '80 and older members. Either will work as both are flat. The 203, 205 and 208 t-cases were all employed on these flat crossmembers. All will interchange with the other.
The '85 and newer crossmembers are a different design. They look like "double humps". You cannot use an '84 or older t-case adaptor on the '85 and newer crossmember.
1 ton crossmembers up to '84 are flat but different as they are shorter in heigth to compensate for the frame height. Again, the 1 ton members will not work because they will put your t-case up higher if you use one on anything other than a K30/3500.
Copy and paste from my post on the post-your-part-numbers thread:
Tranny/case mounts @ Autozone 2 pieces: #2107 and #2108. You need 2 of each, 1 set for each side of crossmember. Made all the difference after swapping out oil soaked spongy original mounts. These are for 700r4 and np 208 combo 82-85. May fit other trucks.
Right off of Energy Suspensions site Click me for list of Poly Bushings I run their greasable swaybar bushings and they work well. I ran their bushings on stock springs for 2 years and they still look good (in my yard). I run Autozone rubber on trans mounts as that what my motor mounts are.
Transmission Mount (V8- automatic transmission)
K10, K20, K30 Transmission Mounts (2 per set)
Motor & Transmssion Mount Set, includes 2 motor mounts & one transmission mount (V8 w/automatic transmission only)
K10, K20, K30 Transfer Case Torque Arm Mount
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