As I was pushing in my new door seals 1/2 inch at a time, I started thinking about what tool could continually push in a thin piece of rubber. Then I remembered my old screen door cord installation tool (a handle with a little metal wheel on each end). I pulled it out and the job went much faster without worrying about damaging the new rubber seal. Start the back edge of the seal into the channel (meaning the outboard edge), and then use the slightly grooved end of the screen door tool to push the other edge in as you roll along. Worked great!!