Finally getting around to putting down vinyl plank flooring and would like to tidy this up! It's a Starmaster 6 1978. Anyone know where to find something like this?
I would patch with neat tape strips and paint it. I have used aluminum tape to fix plastics. Other tape may work espec w plastic paint. I jury rig stuff like this every once in a while and am usually pleased with results. Ymmv.
I'd make two wedge-shaped pieces of wood, one for each end. The wedges would be as tall as the opening, with the thick end being as wide as needed to clear the wheelwell bulge at the bottom, then tapering to nothing at the top. Then you could use a single flat sheet of metal tin, flashing, etc without having to do corner bends. If you want it fastened more secure than just at the two ends, you could put one bend at the bottom with a 1/2" lip coming out onto the floor so you could screw the front down onto the floor.