265 will fit the back fine. The front, not sure.
My first van was a 95 1-ton, a beater with some rust. Rather than buy tires I took a set off a Suburban I had. They were a few sizes bigger and on turns they rubbed at the bottom of the front wheel opening, by the rocker panel. My solution then was to get a sawzall out and cut the bottom corner off about an inch back. But I don't remember what size tire they were.
Oh, this is a thread from 2019.