As I built the Zephyr TD I was interested in keeping cost down. I discovered that at a nearby construction site they were throwing away vinyl sill pieces from an instalation of replacement windows. The job boss said I could have them. I collected an arm load and went back to by building one happy camper.
Using a table saw I cut these down to size and trimmmed the door and bottom of the walls with this found trim. Since I couldn't figure out how to bend the stuff I still used aluminum on the hatch. But I didn't want to aneal the metal so I took an easy way out. I cut slots in the side that would receive the bend of the curve. Hope the pics are self explanitory
It was free and it worked for me...
Dee Bee