The correct way to do it is to cut it out and then weld in patch panels. You put a big blob of body filler in there, backed or not it will crack out. Body filler should be no more then an eighth inch thick and that is stretching it.

Here is a good bodywork web page.


http://www.autobodystore.com/home.shtml

David Fritzsche
1990 Ex-Cab V-6,5-speed, with a few mods
04.5 CTD Dodge 2500 Ram--Tow Rig
Roseville, CA

"Serenity through Sobriety"