Increase Axle Splines #, change drums?

[BullittStangV8]

Simple question guys,
If you upgrade from 28 splines to 31/33 splines, obviously you have to change the diff., but do you have to change out the drums as well? Obviously with disks you dont have to, but I'm unsure about drums, as all my other mustangs have been disks. I couldnt get a concrete answer with a search.

 

[BlownFiveLiter]

As long as your new axles are the same length as the ones they're replacing, I don't see any reason you'd need to replace the drums. You can go 5 lug and still keep a drum setup in the rear, actually.

 

[Fett]

Nope, everything else is reusable.