I don't know if it's too late to chime in but I've been doing IDI swaps for a few years now in Dents, depending on the Chassis being used it can vary from easy to hard... I've had a lot of luck using the NP435 and NP205 as opposed to the ZF5/6. The OD and closer range Trans is nice on the road but off of it I found the NP is a lot nicer. I'll post some photos of the bare frame from the last IDI build I helped with, the kid did the motor mounting low which I liked but he got lazy when he went to put the mounts up and got a little weld crazy... I would have bolted them up myself.

Till I get back home here's a crappy video of his 77.5 4x4 right after we finished the install.

Idk why but we put Highboy on it even though it's not and it was a 77.5 truck... I've done a Highboy or two also but it's a lot more difficult of a swap

http://youtu.be/F8VH7UAf2fk

 

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