At one time I had a NP435 for a Ford. I think the input shaft could be replaced with a Dodge input in a few minutes. Ford applications used two different input shaft lengths. It was so easy to remove the input that I would remove it and use it for an alignment tool.
As I remember it, there were some tabs on the transmission that would have held the bolt holes for a Dodge application but mis-alignment could spell disaster (if you drill new holes in the transmission).
If that bearing retainer that holds in the input shaft and bearing is a tight fit inside the bell housing, it might not be a huge alignment problem.
Bear in mind, I never got around to testing any of that out.
Call either Advanced adapters or Novak they will be able to tell you all you need to know.
The issues here are
1) bolt pattern on bell housing is different
2) input shaft is different
3) output shaft is different
4) tail housing may be different.
Is this for a 2wd or 4wd?
if 2wd you'll only have to worry about the input end the output end would be less hassle as the joints and driveshafts are easy to interchange and find a match, or at worst have a custom drive shaft made.
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