91 GMC, dually, bodywork and 6.2 diesel questions...

[MR4WD]

I'm looking at getting a 91 crew cab GMC. Last year for that style (V3500) It's pretty much the truck I've wanted since before I could drive, but it's single wheel. If I do purchase it, I WILL convert it to a dually, which shouldn't be a problem. The only thing I'm having difficulty with is finding aftermarket dually rims greater than 6" in width? I'd like to run 35's (the truck presently has 5 new 35x12.5x16's or whatever that works out to in metric terms) so I'd need to buy two more tires and 16x8" dually rims.

I realise that I could convert 6 or 7 16x6 steel rims to 8" fairly easily, but I'd like to run aluminum rims mostly for aesthetic reasons. I've sifted though a few websites, but manufacturers seem to concentrate solely on 16x6" wheel sizes? The other side of this is would a 35x12.5 run on a 6" wide wheel? I would guess no, but I've never seen or done this.

I can get outrageous deals on alcoa wheels, so I may go with (4?) new wheels and run a set of 36" michelins, which I could probably get for cheaper than a few new 35" bfg's. I'm aware those run acceptably on a 6" rim. While the tires will probably wear like iron, I find them a bit narrow for my tastes...

I have no requirement for an 8' bed, so I'll probably chop the frame and install a shortbox. Would dually flares fit on a shortbox? What sort of problems may I encounter?

I really have no experience with dually's in a personal environment. The truck I drive every day at work is a dually, and I usually make it my personal truck but I've never owned one.

Lastly, the truck has 60,000 miles on it and the original (no doubt!) 6.2 diesel. One of my work trucks had a 6.5. While quite enemic it was great on fuel, which is an underlying outline I have made. Down the road, I'll convert it to a 12 valve cummins and bomb it, but for now I'll settle for the fact it's got a 6.2 with an upgraded snail, down pipe and exhaust. What sort of power band do these engines operate in? The truck currently has 4.10's and a new 4L80E (with a 205!!). I shouldn't have a problem trading the SRW Dana 60 and 14 bolt for DRW versions, since everybody seems to have those. In OD, with 35's at 70 MPH I'd guess I'll be around 19-2000 RPM. Would the 6.2 cruise with a meagher load at that RPM? (a bed full of work gear for a few weeks) Or would it kickdown into drive all the time? An idea may be to trade up to 4.56-4.88s? I like to think of the 6.2 as a 350 that turns half the RPM, but I'm mostly unconfident and inexperienced with this motor...

Thanks from anybody who can offer insight with this truck,
Chad.