4" to 4.5" Bolt Pattern on a 7 1/4" Rear?

70Valiant said
Yes that is definately a 7 1/4" rear. No you can not take axles out of a BBP 7 1/4 and put them into your SBP 7 1/4. The axles have a different taper and different bearings.
you need to look for an A-body after 72 with disks and a V8(preferably with a towing package) to find an 8 1/4. That is your best option for getting BBP.

So if I find such a rear (8 1/4) as mentioned above, that will or will not be a direct swap of axle shafts? The bearings and all would swap out without any issues, or do I just say screw all this and get the adapters for the rear wheels and leave everything as is.