My dad had a 49 1/2 ton when I was a kid that someone did a butcher job of installing a car rear end under. The car axle was too narrow, so the body would rub when the rear end bounced. Maybe you can find something that is the right width and make it work, but the clown that did this job sure didn't. I suspect there will be others to tell you what you need.
There were some s-10 blazers made (85-87 comes to mind) that I'm told were pretty easy installs.
Good Luck!
