Eaton/Rockwell rear end ID?'s

[Backroads]

I recently purchased a 71 Chev C20 LB 2wd w/sm465. I have purchased all apearently available literature for this truck but am unable to find any info in them on ID as well as repair/parts info on the equipped axle. I also couldn't find anything in the manuals on the sm465 four speed, but I did find info for it in some of the off road sites, particularly Novak's.

I believe the axle is an Eaton or Rockwell product, it has eight lugs and the axles are floaters, but I can find no numbers on it. A rather large axle for a 3/4 ton in my opinion. The center section has a pot cover on the back, and the center section in front is also removable. I have been to several off road sites looking for info on this rear and most just skim over it with no real info or way of ID'ing the axle.

Any way of positively ID'ing this axle?
Any source for info on these oddball rears?
Does this axle, or were any equipped with limited slips?
Can they be retrofitted with a limited slip?

Thanks in advance for any help.
Marty