Worked on this today. 2'x4' sheet of 0.025" aluminum sheet from Lowes. Used a good door panel to make a pattern and cut it out with a jig saw. The window crank hole and door handle hole index the panel, then drilled the three holes for the arm rest screws which I use to center attach the panel whether or not I use the arm rest. Next I'll use sheet metal screws around the perimeter. The old, tired panels were already held on with screws so I just have to try and match the holes already in the door. This is all the same basic procedure I did for the spider doors. After it's done, it can drip rain water all it wants into the door and the panel won't be affected. Also more in tune with the theme of my interior.