I have to say up front that I stole this idea from Kevin at Wagongear.com. I was interested in getting a set from him, much nicer than these plywood jobs. But for this old cruiser, I couldn't justify the expense. Plus I needed a project to work on. I used 3/8 plywood and 5/16 hardware with nylon locking nuts. I used weatherstriping (for home use, i.e. doors, etc. bought at Lowe's) on the access doors and around the entire sealing edge on the back. The main function of these is to keep the dust out of my cab. The Qps are rusted out and a lot of dust was making its way in through the leaky old interior panels. No dust no more.