Let me guess, 255?
I have a 8.25 Duster and spacing looks exactly like that with a .25” spacer. I would like to see if 275’s would be doable with the relocation. I just purchased a kit and have a couple A-body 8.75 housings to choose from.
275’s are doable without the 1/2” offset although it’s VERY tight. With a 1/2” offset 275’s on a Duster have good clearance as long as the backspacing centers the wheel in the tub.