The advantage is:
1. It probably will work.
2. Nothing else has worked.
3. I've removed plenty o'rivet. Not a big deal.
4. Getting the bracket to the bench will enable getting the nut off without damage to stud or threads or whatever.
5. I don't have a clear idea of the working space. I've looked at chassis on the internet as best I can. Sounds like if he ever gets it off, a new fight begins to install new stud/shock. I guess asking for pics was too much to ask for. Even as an engineer who made a career out of fixing problems, If I can't see it, I have to do my best to keep coming up with suggestions.
They can be ridiculed, dismissed, doubted....or they can be tried.
I will leave this to be determined by paranormal activity.