Step Side Bed Questions, Please Help!

[dtlilly]

Background:

I have (2) 9 foot long step side beds complete. I want to disassemble both of them and use the best parts to make one good 9 Foot step bed.

Problem:

The steps and fenders use a 1/2" nut on the backside of a philips headed carrage bolt. As soon as I get the nut turning, the whole carrage bolt turns too. I am doing this alone, so I can't get someone to hold the carrage bolt with a philips, and even if I did have help, I doubt anyone could hold the philips screwdriver in the slots, while I'm trying to get off the rusted nuts.

I do not want to damage anything here. I have a cutting torch, but I'm scared the heat will mess up the flanges. I am also worried I might cut through the part rendering it junk in my eyes.

Any ideas?