Guilty as charged ;>)
It was made by an aircraft mechanic in Dallas. A man named Mike Boland who used to frequent this list, had a few made and was kind enough to send one of those to me. It can be easily removed, turned around, put back on with the nut and allow the flue to vent. It sits snugly just inside the rubber boot around the vent so it does not allow anything to penetrate into the flu when in the  "cover" position. I'd go out and take a pic but my van is "shopping" (will get it back tomorrow) having a new starter put on .... warranty starter at that.
Not a closeup but gives you a pretty good idea of its application:
http://groups.msn.com/BobsPhotoShare/87westysyncro.msnw?action=ShowPhoto&PhotoID=819
 
.... and all the time I thought those little footprints outside my van were mice ... how'd you do that Richard?
 
Bob> Bob Stevens is being suspiciously quiet here....> > He has a *stainless* vent cover on Passion Fruit.> It requires as drill hole and a stud on the stock> outer plate. Pretty slick. I've lurked around> his van at night, thinking of stealing it, but he> stays up later than I can, listening to satellite> radio.> > Maybe he'll post a picture and recall where it came> from. Or maybe he'll just chuckle and delete this> thread....> > Richard> Boulder
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