Floor pan repair

I have a 66 mustang that po welded in new halves OVER the old. Theres no way to separate now. What would be the best way to repair the old ones? They are visable u.nder car They are not terrible, just have some rust holes in them.
     Thanks  

While not extremely difficult for a skilled person, floor pans are a "Bear" to do because they have so many other things attached to them. I recently watched a Hot Rod Mag DVD that showed how to do a pan change on an 60's Olds (same concept)and you might want to try to find that DVD so you can see first hand what it's going to take. My  initial opinion for you would be you'll probably need to cut out both sets of Pans so you get the proper fit and look.

(I'll post the actual name of that DVD by tomorrow if you or the forum folks want to inquire about it)

The name of the Hot Rod DVD is Dream Build Drive  DVD library and the disc is labeled Complete Bodywork and Sheetmetal preparation. It has number 65003D on it also.  

If it were me, I'd cut out everything and weld in a one-piece pan. They fix a lot of problems and there's actually less welding since you're not doing a left and right pan (long or short) and welding them all around.

If the frame rails are solid you can easily cut out the old metal with little worry of any flex. Just use some strong jack stands placed on the outer rockers and at the ends of the frame rails front and rear.

HTH...
Mark  
Mark Houlahan
Technical Editor for:
-Modified Mustangs & Fords Magazine
-Mustang Monthly Magazine

1965 FFR Roadster 427W/TKO-600 5-speed
1966 Mustang 289-4V/C4 Auto
1968 Mustang 4.6L Three-Valve/5R55S Auto
1990 Mustang 306/AOD
2001 Ranger SuperCab 4x4 3.0L V-6/5R44E Auto
2002 Explorer Sport Trac 4.0L V-6/5R55 Auto

+1 on the last post. it just makes good sense.  

the full floor pan is not too bad to install, a lot less welding than two seperate pans for sure, but i cant remember if i had to put the floor pan throught the front windshield opening or it fit throught the side door opening thought. if you have a plasma cutter the old pans come out quick, just cut close to the sides, and leave about 1/2 inch around the rest, to get rid of most of the old metal without cutting into the fire wall, or frame rails or torque boxes, , then go back and carefully clean away the rest of the remaining floor with a grinder, you may also want to pick up the upper half of the rear torque box, as the floor is sandwiched between the rear frame rails, anf the upper torque box  

I can't stress enough to review that DVD as it talks a lot about what 54 packman just said. 20 bucks well spent.  

On my '66 coupe, I also thought of putting the full pan in through the windshield opening, but it ended up being a hassle because of the width. I ended up weaving it delicately through the passenger side door opening, the steering wheel and column was in the way on the drivers side....

I don't know why some folks (like the previous owner) will go the the trouble of getting new floor pans and not removing the old ones, it just seems like common sense. I agree that just taking the whole thing out and doing it fresh will make you and your '66 happy. Once it's done it's done and you'll feel better about it.

You probably already know this, but those thick plastic covers that you can get to cover the hood vent are a good thing. Those vents are the main source of rain and water getting in the car and rotting the pans.

Good luck!!  

the cowel should be checked as well for leaks, mine was rotted out around the fresh air vents too, repaired the ends, and made new top hats to go through the cowel, welded it all up, then fiberglased the lower part of both ends so its completly sealed now