Something missing in my 8.75. Axle slop

--- first off it looks like your cross shaft is damaged from the axles being jammed into the cross block -- you may have to run a file down there to bring the diameter of the hole back to what it was in order for the new thrust block to fit --- if you can't then the carrier will have to be taken apart and the center block repaired.

--- if you are using the stock tapered bearings with the end play adjuster on the right side axle the thrust button can be installed without tearing the center section apart.
--- get a new thrust button and retaining pin ( Mancini Racing has them )
--- turn the center section on its side and install the one half of the new button with the pin installed ( one end flared out or kit may have a split pin ) into the cross shaft hole.
--- install an axle shaft or other round stock into the side you just placed button and pin into to keep it from falling out
--- carefully turn the unit upright to the other side keeping pressure on the axle shaft or round stock from backing out and l having the retaining pin and block fall out
--- now fish the other side of the thrust button in using a magnet or long jawed needle nose pliers over the retainer pin
--- once you get the other side in place over the pin simply peen the end of the pin to flare it out --- if the kit had a split pin no peening is necessary simply knock the thrust button half over the other half of the split pin