These from Dr. Diff seem an easy install but, can't understand the reasoning why he couldn't install the tapered bearings on those axles and I don't like the threaded bolts for lugs idea.
Screw-in studs are very common on aftermarket racing axles. I have them on both my 9" swapped rears. I love em.
Also, some aftermarket axles come with both 4.5/4.75 patterns. Screw in studs makes changing patterns easy.