I have a '69 coup and I need to replace both floor pans from the front seat toe kick to the back of the back seat foot well. I've already patched the one small bad area under the back seat, so I won't need to replace this area or the tunnel. My question is, since the car is NOT a convertable, do I need to add any temporary bracing before I cut out the old pan as long as I replace only one floor pan at a time?

 

Its a good idea to put some bracing (spot weld) when replacing the pan. However, if you are only doing one side at a time the body should hold - if you have the material and the means its better to do it now instead of finding out you should have when you go to hang the doors.