Rear axle upgrade from SBP to BBP

Just went thru this on my '69 Dart. Assuming this is an 8.75" rear end, with 7" wheels you'll need EDIT: 4 3/4" R.S., with 8" wheels you'll need EDIT: 5 3/8" R.S. Of course every car is slightly different. EDIT: I mis-remembered my actual dimensions. I just looked at the invoice. Sorry!