Extention of belly pan....
You can see they extend the sides of the belly pan back to the frame crossmember. They attach to the crossmember at the rear with two threaded inserts that were already there with bolts in them when I got the van, didn't know what they were for, do now. The top edges attached to the underside of the frame with more threaded inserts and they attach to the belly pan with snap in 1/4-20 speed nuts and short bolts. As for function, not only will the protect the brake lines and ignition from splashes, I have noticed a drop in engine temperature, they seem to act as air deflectors pushing air up and over the exhaust manifold on the drivers side and forcing cold air up to the air cleaner on the pass side, or they are forming a tunnel that forces the fan to pull more air towards the back and out of the doghouse? However they work, all I know is that my temp gauge is reading 5-10 degrees lower at all speeds since I put these in. After installing them, I can see why so many are missing, they were a F***ing PITA to get in place, the holes didn't line up and they needed twisting and massaging to get them to fit, I can see why many servicemen probably left them off! As for the rarity and need for these, they are made of flat sheet metal with all angled bends and I would think could be easily copied and fabricated out of aluminum sheet or duct work by anyone handy with a bending brake?? Has any one tried this? PS, I made a similar post over at VCVC and thought some here would also like to see these...