7.25 to 8.75 swap Dodge dart 1965

Ive recently collected a 8.75 rear end from a 70’s charger that I wanna swap in my 65 dart instead of the 7.25 rear end.

but the 8.75 is much wider than the original 7.25 rear end.

is the only thing to do narrowing the 8.75?

I think the 7.25 is around 51 inch and the 8.75 is around 57-58 inch

help