The horizontal panel above the cab (where the overhead storage bin is located) has a nice sharp unfinished sheet metal edge. I first tried to glue some vinyl material around that edge and tuck in into the seam, but the glue didn’t hold. Next up was to get some actual panel edging. This worked much better. Simply cut to length and push it in place.
Trim-Lok Edge Trim – Flexible, PVC Plastic Edge Protector