A518 46RH rebuild
There are are still details I am sorting out but I wanted the overdrive as well. Quick searches for replacement trans mounts did not make it totally clear if my old trans crossmember would work with an overdrive, but I now think it will. The older ones are clearly not going to work because they have the very small loop where the old style 727 mount goes. A 92 D250 came available so I grabbed it’s crossmember because already had a 46RH trans.
My Ramcharger crossmember is shaped similar to the 92 D250 but definitely different. The Ramcharger uses a bunch of spacers to position the crossmember on the frame. The 92 D250 mounts solid to the frame with no spacers, so it looks cleaner. It appears they would place the trans mount in the same spot.
The holes in the frame of the 92 D250 and the 89 Ramcharger are not the same, so crossmember will not bolt right in. But the frame holes could be welded closed and redrilled.