I went this way with the 8.8 in my Dart, if you can find a ranger 8.8 it's the right width already and the center isn't offset.
On another note if you have a mild motor, 300hp or less on street radials I bet a 7.5" would hold up fine - they're much stronger than 7.25 chrysler rears, V8 mustangs came with 7.5's from 79-85 and they hold up ok until you put slicks on them.