Very new to the unibody world- so pretty concerned about the preferred approach to repairing the frame/chassis on this newly acquired 71 Roadrunner. I have not had much opportunity to dig into the car- but I do know that the front driver's side frame rail appears to be a candidate for replacement. The right-hand side is not nearly as corroded, but the RH side of the torsion cross-member is by far the worst area of that failed component. Anyway, I'd appreciate advice on a safe approach to disassembly of the vehicle in the process of frame repair/replacement. I am unnerved by the nature of unibody construction- even wondering if removal of the bumpers reduces the stability/or increases the chance for the geometry to wander while trying to repair. Same question for the rear bumper, as those subframes appear to be in need of attention, though not sure whether this could be a repair in lieu of replacement. As noted, the torsion cross member has failed, and the front floor area is generally gone ~has some sheet metal riveted atop the rusted-out flooring. That field-expedient improvement appears to have really accelerated the decomposing original floor (...thinking the bench seat may now be a structural element).
