Here is a quick-guide on how to replace the front differential bushing without replacing the whole crossmember. Let me know if you have any questions.

I had troubles finding a video guide, so I hope this helps others!

Links to what I used:
OEM-style bushing: https://amzn.to/3vrXh5K
P'Blaster penetrating oil: https://amzn.to/2QHo9jb

 

The nut of the front differential bushing (not the one on subframe/crossmember) is spinning (my H3). I see that it was (factory) attached to frame, but has come unattached. Very small opening, not allowing me to put box end, or any other, wrench, so as to hold. Any ideas?

 

Spray penetrant and use a big **** screwdriver to wedge the nut against the frame.

 

I'll giv'er hell.

 

Welcome to HF.

Please READ what the rules are at this forum before posting as you would then know that digging up OLD THREADS to tack on your question is NOT how we do things. Not how most any forums do it either. READ: Old Threads/'Necro-Bumping'

You also do not need to post more than one question on the same topic, which you did in another OLD Thread, which I now closed.

Did you search the interweb for the answer to your question before posting? If you did you would see vids, and on line products, some with install instructions on how to replace the Front Diff bushings. You need to take apart the at least one lower control arm from the spindle, pull the axle half shaft, remove the bracket that the side busing in question is inserted in, and then remove the bolt and bushing for replacement.

Check this out. H3 D.I.Y. FRONT DIFFERENTIAL BUSHING KIT

 

Thank you for your suggestion. I'm new to the forum, I apologize for my ignorance.
I have searched web, with none, or few instructions on FRONT bushing. I understand removal of mounting plate, but unable to remove due to the nut spinning on the bushing bolt. Removing the bushing is not in question. As seen in MY pic, the nut is unaccessable. Videos on web (few available) already have bolt removed, therefore not addressing my issue of nut spinning.

 

My apologies again, but this is right/passenger side

 

Can you get in there with a welder? Tack the nut to the frame?

 

I've been pondering that. I have MIG, but not able to get mig tip in. I'm thinking stick weld. I don't have stick welder.

 

You need a stick welder, but degrease all the thread penetrant first.

Good luck.