Classic Mustangs have always been cursed with rust and corrosion problems. The most notorious are cowl-vent leaks that result in floorpan and kick-panel rust-out, and the inner-fender apron under the hood where the battery sits. Because lead acid batteries contain sulfuric acid and emit corrosive fumes, they are especially hard on sheetmetal body parts like the inner fender and battery tray. In the past, we've shown how to replace the entire inner-fender assembly. But what if you don't want to replace the inner fender? It's best to keep the serial number intact, which is stamped into the inner fender. And sometimes it's just too much trouble to pull the fender and drill out all of those spot welds.
We visited the Northwest Pony Shoppe in Snohomish, Washington, just outside Seattle, to see how they correct battery-apron woes without major surgery. This is an easy fix for anyone who knows how to weld. And, if it's too much for your talents and abilities, this job can be done by your favorite autobody shop.
We're going to show you how to patch the inner fender. It won't look like a patch, and you'll save time and money in the process. For our repair, Mustangs Plus provided a new right-front inner fender, which is made of the same heavy-gauge steel as original equipment.