Swapped to Muscle - 75 Duster Daily build
If you want vented rear disks and the same or similar width to a ‘67 or so B-Body, you might look for an 8.8 out of a Mustang. Been too many years, but I think you want one out of a Fox body?
But there are two issues with that axle. There are a bunch of brackets to cut off before you can weld spring perches on, and they are (stock) a 4 bolt axle.
I think the 5 bolt axle conversions are pretty cheap, but adds cost to the swap.
Nice thing is, the pinion is centered so no issues with the driveline hitting the mufflers.
Pretty sure a Crown Vic axle is too wide. Seems to me that there is a Ranger axle that would work (can’t remember if it is width or spline count though), but they are a rare as an A-Body 8.75.
Food for thought.