Thanks to Alan for the mudflap idea for when I ( dread the thought ) TOW my Roadster to Florida in a couple of weeks. I figured a temporary mud flap system for the back of the truck might be a good idea and Alan gave up the idea of sourcing the rubber mats from Tractor Trailer Sales Facility.
Nicely enough the local Facility gave me three rubber sheets to work with. $10 for an aluminum angle and about $5 more for fasteners and everything is held on by a trailer anti rattle clamp that I had anyway. Not fancy but should work. Test drive it tomorrow to see if it needs any stay bars or the like. Thanks, Alan !