Removing torque boxes?

[Gigantopithecus]

Is there some secret to getting these out without having to use a pound of c4? I know there's spot welds to drill out, but is there anything else that I need to look for? I'll be cutting out the toeboards since they're shot as well. I know that will give me access to the top on the box. Maybe I'm missing something, but they just will not let go of the front support rail. Tools on hand: drill, air chisel and sheer, angle grinder and cutoff wheels, sawsall(doubt I'll need it).

 

[buckeyedemon]

on mine (69) the factory put some small little stitch welds to attach the lower side of the torque box to the front frame rail (on the outside in the fenderwell area.) thus they were attached by more than just spot welds.