Transmission Gear selector issues

Column shift, I have to assume.
Duster linkage, I also assume.
D250 trans. selector arm, again assuming.
Given the above, the selector arm on the (truck) transmission is most likely the wrong length to work correctly with the Duster linkage. Use the one off of the old /6 904 if you still have it.
If any of the above assumptions are not true, you will need to give more detailed info about your setup.