Good Axle or Not?

Well i got a hold of a potential axle to put in my 71 Demon. Little did I realize that its Not an A Body axle. I was wondering though if i could get a little clarity on this rearend and if the center case is good to use

It has a cast number of 1634985 and a number below it that reads 2 3 then what looks like a circle then a 9. It also has a large 2 and a large X at the top left.

I have no idea what this is or what car its out of. The perch distance is approx. 47 inches

Help Please

1634985 1957 - 67 ABCD 8.75 10 studs/no rear cover

year one axle id

http://www.moparts.org/Tech/Archive/axle/16.html

Assuming its an 8 3/4, the info from the archives can help. Look near the bottom of the post to find perch widths.

11634985 is an early version of the 742 case