The "chassis" as you put it is really only a stiffner for the floor and bulkhead - Ive never come across stressed panels in car body design - just chop the affected section out, and replace with new - 16 gauge steel will probably bit a bit on the heavy side, but will certainly do the job.
I wouldnt worry about the structure ofthe car while chopping it about - the inner and outer sill should be more than adequate to support the car while you let the repair section in.
Have a go at it, welding car bodies up isnt a hard thing to do, so long as you clean the rust off completely, and make your repair section fit well.
I wouldnt worry about the structure ofthe car while chopping it about - the inner and outer sill should be more than adequate to support the car while you let the repair section in.
Have a go at it, welding car bodies up isnt a hard thing to do, so long as you clean the rust off completely, and make your repair section fit well.