Brent I have been using this type of setup for awhile now and have had great
results. I use four telescopic poles and three or four spring clamps.  I set
two poles in the grommets at the corners furthest from the van, and the
other two in the second row of grommets nearest the van. I then clamp the
remaining flap of tarp to the rain gutter. This type of setup allows me to
drive away after unclamping the tarp from the rain gutter and leaving the
tarp free standing, to be docked with latter. Scraping marks around the
passenger side tires before driving away will make for easy "docking" upon
returning from a day trip. the poles I have are 8ft max and 4ft when
collapsed and store on the floor in front of the fridge /sink area, and
don't affect opening the fridge or cupboards. I dug up a picture of this
setup and will mail it to you personally, in this picture I'm using a center
pole for max. headroom. Jim