A body 8&3/4 housing, not sure if it is OE or if Moser shortened it. Dr diff A body BBP axles. 5:57 non sure grip with welded spiders (for the stock car). the axles will not insert all the way into the housing. on the drivers side the bearing/race will barely go in & on the pass side the axle/bearing/race is slightly off center & take some pressure to move it slightly to cantered & isn't close to even getting started in, something ain't right. I have no seal in the driver side, I took it out as I thought that might be the problem. iirc I had this pumpkin in another housing with no axle issues. I inserted the dr diff axles in another bare housing & they went in smooth a silk. thank you for your time. RR
First, confirm that your housing is the correct A body width.
An accurate 8 3/4" rear axle width list
If that is correct, then start wiggling/twisting the axles to see if you can get them started.
If that's a no-go, and they fit into another A body housing and center section without any issues, there's only 2 things left.
1.) Your housing is bent.
2.) Your spiders weren't welded up straight and centered.
To check #1, take it to a rear end shop and have them throw it on a jig to see if it's square. If it's not too far out of whack, they can usually straighten them. If the housing was narrowed, they can check that the housing ends were welded on properly.
If #2, you'll have to start over with a different carrier and spiders- this time weld them up with an old set of axles in there to hold the gears in place as you tack them up.
Since you had the center section in another housing and the axles fit fine, I'm leaning towards #1, the housing is tweaked.