how big of a project is it to install a new floor pan (driver side) in a car. the car is on the road and not tore apart. Is it possible to put new one in without tearing the whole car apart?

i should have been more specific. just floor pan area in front of drivers seat up to the point where it angles up behind brake and clutch pedals to the firewall.

You can do that in the car. It will be a bit more work to get it done, but far less than taking the whole car apart to do it.

I suggest you get a good reciprocating (sp?) saw such as an air saw or saws all. Get plenty of blades. This will generate far less metal dust and sparks than a standard cut off wheel, or whiz wheel. Those work great but will make a mess of the interior on the car.

You will cut out the old pan and place it on top of the replacement pan. Then trace a line about an inch or saw larger around on the new pan, then trim the new pan down. Grind and clean the mating surfact on the car and slip the new pan in place. You can now tack weld it around until it is secured.

Since you are doing this on an assembled car, take your time and weld so that you eventually stitch the welding seam up. Lay a blanket in the car (watch for fire), and grind down any high spots that will be a problem.

Get some seam sealer and smear it on both sides after they are cleaned free of grease and oil.

Apply some primer, paint, and some rubberized undercoating then reassemble.

Now there are a hundred other ways to do it, but that is how I would do it in the car.

Good luck.

gotta love this site. thanks so much, i dont look forward to it but unfortunately it has to be done. 37 years have finally caught up to it and beginning to see some pin holes in it. Thanks again for your help.

one more question. my body guy tells me he will be able to patch in the new front pan, weld it, grind it down, paint and coat everything and you wont be able to tell a new pan was patched in.
Does that sound reasonable? Im just paranoid about seeing signs of patch job. Want it to look perfect.