Like the others have said, you'll have to take the belly pan off, get access to the frame. The bolts most likely have been bent to prevent the nuts from vibrating and coming loose or off.
I used a cut-off wheel on a Dremel rotary tool, with an extension attachment for hard to reach areas. I got the extension at Harbor Freight. I wonder if the new multi-tool would be even better, not so much slinging metal shavings all over the place.
I'm sure you are already doing so, but, be sure to wear good eye protection. I also wore a hat, sleeves, and buttoned my shirt all the way to my chin. Metal shavings can be very irritating, even painful, in my noobie experience.
Originally Posted by jaminalee
I am currently replacing my sub floors and am soo stuck. I can't for the life of me figure out how to get the elevator bolts out of my floor! I've tried the wiggle method but the head of the bolts underneath are flush with the plywood so there's no way to get a hold of them to hold them tight so I could unscrew the nuts on top. I have the belly pan off, all interior wall panels removed and am so ready to get the old rotted sub floor OUT! So please if anyone has any advice on different ways to go about it please help!