Removing body bolts when the cage nut spins?

[Richard150MPH]

I would really like to get the body off of the old frame soon.
Not sure what tool to use for getting the last bolts out since the caged nuts are spinning.
Have to work by myself which probably makes it harder.

Grind off the heads?

With the body off I will be able to make some important measurements needed to fit the IRS.

 

[JohnC]

Your gonna have to cut a little window in the floor above those spun caged nuts. I imagine that would be the best way to get the bolt out.
I got lucky. All mine came out with little effort.

Good luck

I hear the way to go is cut basically a square window - actually only 3 sides of a square and peel back the metal. Weld her back up when done.

 

[1969chevmalibu1969]

I drilled a hole in mine when it spun and I plan on welding or putting a plug.

 

[1969chevmalibu1969]

If I would have know about the way John said three cut slit would have been better

 

[Shaner]

I would think a nice sized hole over top the nut, prime the metal so no future rust, and then cover with a plastic plug would be a great setup.