I think I started letting go of my worries when I replaced the drivers side cowl on my '51. The bottom was rotted out, but at the seam, where it is "sandwiched" and spot welded, I figured it would also be rusted and easy to take apart. Boy, was it a bear! My car was an AZ car but had the opportunity to have fine dust and dirt settle in those lower areas. Which then trapped moisture. So, lesson learned was to coat as much as I could with epoxy before welding together. Then, make it regular maintenance to keep the drain holes clean.
