15x10 on Duster

I have a 66 B-body 8 3/4 under my 74 Duster. You will have to drop a plumb bob down from the top of the quarter lip and measure to the inner part of the car where the wheel would hit first (you can use a straightedge for this). This will tell you the maximum width of tire. From there you have to measure the front of the drum surface to the inner part of the car to get the back spacing. Then you can measure from the front of the drum surface to your plumb bob to get the front spacing. The front spacing should be the same as taking your maximum width minus your backspacing number.

From there I came up with a spreadsheet to tell me the %'s between front space and back space. For example 15X10 center line I just looked up have a backspacing of 4.875. That means the front spacking is 5.125. So with an 11 inch tire you will have 5.64" of tire in the front torwards the fender lip and 5.36" of tire towards the innner fender/frame rail. I'm pretty sure this won't fit as it will hit the fender lip.

I went with a 7.5" with 5" of back spacing with a 9.5" tire. It will not hit the fender lip. I could get a bigger tire under there if I had more backspacing and a bigger rim.

I think the only 10" rim I found with a lot of backspace were the Welds. I wanted Centerline polished so I opted for the smaller rim.

I think I had 12 inches of clearance. To get a 10 inch rim you would probably need like 6.5 to 7 inches of back spacing. Then you also have to take into account the tire width. I'm not saying it won't work but there is a lot of measuring that needs to be done.

Good luck!