Nice yob. A couple thoughts.
-I would have thought the roller would do more good down in the middle where the tread is hitting the structure during turns.
-Do you have a game plan for returning airflow to the body side or is it just going to dump off like that?
Anyway, I like to see what you've done. This mod is looking easier and easier as more people do it. The Probe should see one in the not too distant future; a local surplus store has a few extra long hinges!
Keep it up.