Anyone running 15x10 rears on their Duster/dart sport?

Sounds like a lot of thinking, measuring and searching for the right stuff.

Yeah definitely. If you want to max out your tire size you have to take everything into account. i start with the tires I want to run, which sets the rim size. Then you have to look at backspace in those sizes, which depends entirely on the suspension and brakes. So, you either pick the rims and tailor your suspension to work with that backspace, or pick your suspension and brakes, and tailor your rims to work with that. Either way will limit your options.

And everything changes with the wheel diameter. Most 15" wheels are available in "0"offset type backspaces, while 17/18" rims are more popular in large positive offsets. The "0" offsets are good for stock width A body 8 3/4's, but don't work on the front with wider tires, especially with most aftermarket brake kits. The higher positive offsets are great for the front because thy fit better and the larger diameter wheel clears the tie rods, but they need a wider rear axle or large spacers to work in the back.

On the Duster/demon body that's pretty easy though because a 68-70 B body rear fits the bill. In my case, my car had a 7.25 stock, so the B body rear was not only better for my wheel choice but a lot cheaper and easier to find than an A body rear.

And it's only the A bodies that are mismatched like that. The E/B bodies work best with "0" offset wheels front AND back.