.....ring gear is locked up so I can’t rotate it to get at the rest of it.
Another reason to look for a replacement differential housing.
If you can push the axles inward to release the C-clips, then remove them, you can unbolt the differential housing/torque tube assembly and pull the whole thing out the front. You'll need to do that anyway to rebuild it if you go that way.
Here's an
exploded view of what you're working on to help with nomenclature. The axle c-clips I mentioned are called locks in the figure. But you'll need to get the spacer around the spider gear shaft out before you can push the axles in. But then again your spider gears are already out, so you should be able to just pull the axle shafts.
[ON EDIT]Take a look at your picture that I added a note to below. This piece may be what's locking things up. It looks out of place to me. But it's been a while since I had my differential out of the truck.
