I assume what you really want it the 5 on 4 1/2" bolt circle.

Maybe you can get the 5 bolt spindles by swapping everything between the ball joints, but I haven't done it, or even compared to see if the suspensions are even close to being the same. It might be cheaper to have the 6 bolt stuff re-drilled to the 5 bolt stuff, but I suspect there may be issues with some of the wheel stud holes since the 6 bolt stuff is also on a 4 1/2" circle. I think your opening up a can of worms, but if you succeed, please let us all know what you did, with the needed part numbers. I'm sure others will appreciate you venturing into this unknown area.

I would swap out the entire rear end for something with the correct bolt pattern, or buy aftermarket axles for your rear end, if you have a 9 1/4. I wouldn't bother with any smaller rear, just swap it out with something that has the bolt pattern you want. Gene