69 Dart Wheel offset

In factory wheel wells, 275 is about it. Your stuffing a 10inch wide tire into around an 11inch space. Trimming the fender lip can gain you a bit more, but its tight. Offset can depend on a few factors with the axle. I'm having to use 5inch backspace 15inch wheels to work with my mods, which includes springs moved in, Dr Diff 5x4.5 axles and rear disks.

Thank you! I think a 275 will be plenty especially if i dont have to do mini tubs and frame work for spring relo kit. So a 275 will work with standard spring offsets? At this time i havent made up my mind if i am going with 15" cop wheels or if i want to do a 18"-20" aluminum wheel. with only doing the offset shackles do i have to use a 15" wheel or does it not matter?

Thanks