8 3/4 cut down

The 7 1/4 only has 2 1/2" axle tubes and the 8 3/4 uses 3" so you will need the shock mounting plates. Since you're going to have to cut it and get new axles, you might as well go a couple inches narrower. You could also go with the spring relocation or offset hangers if you don't want to cut the car.