surgical tubing just so the screw threads don't touch the plastic, maybe preventing splintering, maybe not necessary...was about $2 for 3 ft....
rubber washers because it seemed like a good idea not to have the metal screw head rubbing on the purdy paint, and possibly grinding through it over time....on my dirt road. I'll cut down the washers so a ton of washer isn't exposed around the screw head. Maybe both are overkill, but super cheap.
Hope the paint cures much harder over time. Didn't ask about that. When I got my Lexus back, the shop told me not to wax it for 2-3 months as the many layers of paint would take a while to cure. So maybe our will cure too.