Damn!!! Its gonna be sweet rolling on those!!
If I remember the 4" UJ lift cant run the better steering system so I'm sure 6" will be perfect.
I think that mine is right around 4 3/4 - 5 inches. The extra inch will still keep the height reasonable..
I think that the green UJ flatbed had 6" w/37's. I always liked the stance of that thing.
Most really functional offroad trucks keep the lift to the necessary min. I'd bet 90% of the jacked up pickups and jeeps you see on the road are for show and never/rarely see dirt. The exception being some mud trucks.
I'm no gear expert, I think if I regeared my PSD I would go 4:56, but the IDI may be better with 4:88's
Chris built a blue IDI van at one point you should find out what gears that ran. It was a regular van so probably much lighter.
Anway you slice it that thing will be awesome!!