Axial play, how much is normal?

I noticed when i put my car on jackstands that the 8.25 rear has some axial play (wheel moves in and out a bit when pushed or pulled). How much play is normal for a 8.25 rear?

Is it possible to tighten it up by adjusting something..?

Rearend comes from a 74 a body, and is now under my 67 barracuda.
(There is no radial movement, only axial).