Sorry I didn't post this earlier as i was hoping. As per above, here's a van my buddy did for his work. He had to dig up these pictures ..I didn't have them on my new phone either. He fabricated up the rockers and door bottoms out of 304 SS a few yrs ago. They use a few vans for shuttling customers to/from the airport and hotel and their HQ (for training events, etc). They have a handful of vans and he's done each one of them as they got rusty. They use a lot of road-salt up this way in the winter. The company doesn't want unsightly vans, and even new ones get rusted up fairly quick (no budget for new vans every few yrs). And I think when the vans get old they use them for service work around the buildings. IDK for sure. They could probably undercoat them, I think he's told them to, but they don't seem to ...and the vehicles are not his dept, so they probably don't listen??. Plus during covid he needed projects to stay busy! In their shop he has access to a large hydraulic press and bending brake and lot of good metal tools. He made a jig with a 2" wide piece of channel iron and a large round solid piece of steel and pressed the sheetmetal down into the channel iron (24" long) with the press, to make the curve. And a bending brake to do the bends. Then tig or mig welded the 24" sections together before installing. He used to have a picture of the job before he painted them black, but he couldn't find it.
For the doors, he cuts the rusty metal off the door bottoms ~10" from the bottom ..or whatever it takes, and flanges the remaining edge with a flange tool, then puts on the SS he's pre-formed & drilled holes, and just welds the SS to the sheet metal, fills the holes with weld. Then some appropriate primer & light bodywork on the door seams, and painted them. The van in the picture below he bolted the rocker at the bottom in case he needed to remove the inner rocker panel for some reason (also SS). Some he said he welded. Some of the projects are 5 years old now and still look good he says. You southern boys don't have to deal with this (lucky you!).
I know you're thinking about going rock sliders or square tube, that's great. But since I mentioned it above I wanted to close the loop on S/S rockers & door bottoms.
