That will work with two vehicles. But the time of night I sometimes show up, or daytime during the week, there usually isn't a second vehicle with me. I'd prolly haf'ta use a couple of poles to hold the outboard side. Maybe drive in a PVC tube and slip the tarp pole into the PVC. Would have to figure a side panel too (single vehicle).
Me don't need no steenkin camper Davey!
*edit*
Maybe a tarp draped over the raised cap back window, hang over the sides. Use bungee to the wheel wells and the PVC pole system off the back. That way I would have rain/wind protection on all sides except for an onshore blow.
Dave, I saw one of the tarps you linked to. They're good for about a 5 knot wind. Saw one totally tear itself up.