I have seen many discussions of marine plastic whenever someone used or considered something else, so I ordered a 14'x10' sheet from
Boat Shrink Wrap Construction Wrap 14. That was more than I wanted, but ten feet was the minimum length--$2.18 per foot, with free shipping. I bought a heat gun and tonight I tried it out.
I wondered how it would ever work, I needed to be able to attach the lugnuts!
It shrunk pretty well, except at the edges, and where I had slit it to fold around the back. The last picture shows a hole on the edge--that came all of the way from the back!
When I try again I will cut a slightly larger piece, cut out holes for lugnuts, and put a five-pound weight or something to hold it down as I shrink the rest to fit.
We will see how it goes, but it takes a while!