Here are the actual specs for the duratracs in both sizes. 255 is 1.5" taller and .7" narrower. You will need much more cutting with the 255/75, especially on the front bumper with a 19+. That being said, the cutting is really not that hard. If you have to do the pinch seam, I used a angle grinder with a cutoff wheel. Then for cutting the front bumper, I used a multi tool with a drywall bit. Then cleaned up the edge with a metal file. You could also use a razor bland, knife, or sand paper. Just depends on how big you want to go. I ended up with 265/70s on my 2019.