The rear half of the drivers side floor pan of my 72 is rusted and has been poorly repaired. Before I start cutting into it and welding a new panel in place with my gas shielded wire feed MIG, can anyone tell me if and how I should brace the car so I won't screw up things like the door fender gaps, or shouldn't I worry about it since I'm not touching the longs. The car presently is on jack stands, as most seem to be! Thanks, Mike.

Just go slow. If the metal is cool enough to touch your alright. Don't concentrate too much in one area. Move around with the welds and cool with an air hose as you go. I did my longs this way w/o bracing.