I have a a heck of a time with the axle play on my 69 RR. I only replace the seals. I backed off the adjusting wheel and for some reason it will not adjust the play on the left side but does the right side. I put left side in first hit with a rubber hammer to set bearing and then tighting 5 bolts. Any Ideas Help Thanks Tom RR

If you have a early clutch type Dana corp. posi unit in your 8 3/4 you may have a issue with the end play adjusters that slide into the cross shafts in the posi unit falling out when you removed the axles 1969 was a change over year on the posi units used in the 8 3/4 rear ends.
Take a flash light with a pencil type beam and look into the axle housing from the passenger side to see if you can see a hole in the cross shafts, if so that is the problem The end play adjusters slide into those holes and are use to put tension, adjust, the end play, on the other axle
You say it will(passenger side) adjust, screw into the holder, on the passenger side, is the adjuster screwed in all the way out of its holder?
If not adjust it in some more until it starts to get tight on the end play and then adjust for .003 to .010 max in and out movement on end play cold
Good luck, let us know what you find

Turn the adjuster in until it stops, hit the passenger side axle to drive the driver side bearing race against the backing plate.
Then see if the adjuster will go in more. If so repeat the above. Once you have zero end play then back off the adjuster.

The thrust block inside the diff transfers side loads into the other axle on turns and while driving straight. It has only certain amount of travel. The SureGrip unit uses a floating thrust with two buttons and a roll pin. The open diffs use a thrust block.

There is a remote possibility that you may have to pull the driver side backing plate, yank the shaft out a bit then use the backing plate to push the bearing race in to the axle tube. The race should be flush with the backing plate.

3 to 10 end play ?

Me thimks the old needs to double check that .....

ALMOST 20 ... IIRC ? ...

and sea Bee .. it’s good to See that you are not abusing per post smilie limits

found the buttons in the bottom of housing Thanks For The HELP TOMRR