For curiosity and record keeping, here are some casting (and other) numbers off various parts.  I'm only including the 25 and 41 axles, since they're the original ones, and are being reused.

 The 41 axle still has its ratio tag (43/8=5.375).  (The 25 did, too, shown below.  The 27 and 44 did not.)  Also in this picture is a code 9-65.  I don't know what it means.  The 41 is also visible.

 Also on the 41:

This one is the 25.  The code at the bottom is totally illegible.

 Here's the ratio tag on the 25:

 

The 9" brake backing plates (41/25, L&R) all had the same number on them:

 

 This is on the 25:  It's the only one of the four axles that had numbers on the side of the differential away from the cover.  The 25 is clear; I don't know what the 48 means.

I can't see any date stampings on the axles where http://www.cj3a.info/tech/datecode.html says they should be.  There is a "6" stamped on one of the "donuts" referred to in that page, but it's in a bigger font.