If I'm not mistaken you can pull the rear drum and jockey around to where you can drive out the old studs one at a time and pop in a new stud without pulling the axles. As for the lugs spinning, I think that there are several sizes of knurled ends with slightly different diameter knurls.... .486, .580, and .509. The PO might have gotten in a hurry and installed the incorrect knurl diameter which would allow them to spin.
You might give it a try before you pull the axles. Most parts houses carry the various size of knurled studs and if everything else fails Summit Racing has them in 5 packs. Hope this helps.
Dave
