dana 20 or 21

[dodmort]

So In walking around the Transmissions and T cases I have lying around the place . I was lucky to find a fresh 435 (trapazoid pattern and the t case adapter still on it) for very little cash so its at home...(these 435s are NOT getting that easy to find around here anymore). Forgot that i was able to land for free a RAT tranny with the 20 still mated up out of a EB for in May... Mind got to going..... Anyone tried to put a dana 20 on a 435 in their EB or any other ford truck using the ford adapter that I think works with a dana 21 ??? If no Why can you not fill the holes on the bottom of the 435 and re-drill them for a 2 wd Tailshaft....