The NP 205 swap wasn't really a walk in the park, but its pretty doable. It kinda depends on how much of a fabricator you are. If a guy was pretty good with a welder and torch, it might almost be easier to build a whole new crossmember, instead of adapting the mounts like I did. I'll post a
pic of the plates I used to get the 205 far enough up in the frame.
Here you can see the final deal. The upper mount on the driver's side was just a custom piece of plate with web welded on for strength, which I don't have a pic of. It's a great transfer case to swap in--tough as nails, and pretty easy to get parts for. There's several different varities, most of which bolt up to the tranny. The divorced NP 205 like I have is out of an older dodge, I believe. I bought it from a place called
Off Road Design and I'll warn you, its not cheap. I think the divorced NP 205 itself was around 800, plus shipping. I didn't have many options, though, as I had a T-221 with a fist-sized whole in it, a non-driveable truck, and a brand new driver's license. They have a ton of info on their web site about 205's and such. I don't know that you can adapt a 205 to an SM 420 tranny like you have, so that's why I went with a "divorced" t-case, which has 3 yokes on it. Feel free to let me know if you have any other questions.