A lot of the guys from N.Y. State fasten a sheet of ABS or similar to their roll cage. The first one I saw was on Tom Arch's machine from EGO Performance. There are lots of them now. I had my bed liner sprayed (Linex) so I used the old liner from a full sized F250. Fit like a glove on an Avenger 8 wheeler. The spray on liner guys will give you a liner if you promise to cut it up!
Larry, The argo convertable roof costs about as much as a new car did a few decades ago. If i wreck this one the chances of getting another would be nil or less! The plastic protects the canvas when running under branches. It makes a pretty good umbrella if you get caught short with your roof down too. I prefer to run with a bare machine in the summer though.