Wow paul,
That's an amazing story!! I've been through the ringer on these many many times. I was so proficent at it-when turning wrenchs they came to me.
Let's see. I'll say it again- you can beat on the fill plug. The washer under the steel plug is aluminum. Look up the coefficent of static friction for alumium, figure out the tension applied using the factory torque... you'll see you have to overcome lots of force. It's a good thing ... it will not come loose in service. Really, seen lots of wrenchs and they reach for a ball-peen hammer.
Yep- upper bolts would be a bXXXch without lowering the diff a little. No need to remove the 22mm bolts on the subframe rear mount-unless you are replacing it.
You should be able to work the axle in position with a little strength. I'm assuming, you've colapsed the axle completely to squeeze it into place. C-clipped the inside (after replacing the side seal on the diff). Then you need to get the length to increase and fit the wheel hub. YOu can wiggle and pull on the axle and it will move the inner joint. If the splines will touch, I just screw the bolt in the axle and pull with pliers. Done it and it works. Maybe one-handed and wiggle the axle joint.
Now that you know the routine- *next* time it will be easier.
Michael