Thank, OCK. Much useful information, but I'm not sure how helpful in my particular situation. I'm putting late '70s 3/4 ton front suspension and rear end under my truck, as I want it still to be a 3/4 ton truck when I'm done and I want it to appear stock. It's going to be a daily driver for freeways and trailer towing and hauling and whatever, so I want to use fair-sized LT radials--probably 245LT75-16. These require a rim of about 7" width, so I can't use stock wheels anyway. (Were there stock 16" wheels? Mine are 15", and I've read about 17", but not 16".) I've learned that I can install clips in later GM 8-lug wheels and use the stock hubcaps. With the wheels painted black, you'll have to be pretty close to tell that they're not stock.
If I have to use later wheels anyway, and if they are available with increased backset, I can't see the benefit of narrowing the front suspension. Seems to me I'd also have to narrow the rear end, which is a lot more work. I finally found the website I had been looking for, and the writer says the difference in the widths of the frames at the front is 1", which is easily adjusted by using spacers. He says one might want to use van wheels. Anybody got a late '70s-early '80s GM 1-ton van with stock 16" wheels who could measure the backset for me? If I can make my choices of front and rear ends and tire size work by buying a set of van wheels from a wrecking yard and painting them black, I will save a *bunch* of money and time.
Thanks.
Joe
