8.8 swap
Mine (69 Cuda) has a standard width 8.8 3.55 from a 98 explorer which was in the car when I bought it. The spring perches you do have to move because an explorer mounts different.
Right now it's got 18x8 2012 Mustang GT rims on it with no issues up front or back. There is about a 3/8 gap right now on each side from the springs and the lip hasn't been touched.
I just ordered a Doc Diff spring relocation and I'm picking up another 8.8 for $150 that has 3.73 lsd to use the LSD out of and passenger axle when I narrow it. I'm not gonna mini tub either because from what I'm reading on here I can get a decent width tire with no issues at all!!!
I also have a stage 3 Overdrive 4L60E from Silver Sport Trans that I'm putting in as well!
So with a 3.55 lsd and an OD I should have the best of both worlds....Hopefully!!!!!