I too, mount a Yakima rain gutter style Yakima rack onto the rear door of my 84.  I'm a bike racer and I live in the Columbia River Gorge, probably one of the windiest places in the US.  So having my race bikes up on top and busting into a 40mph headwind (an average summer day) would be slow going.  Normally, they ride inside, but when I have a 'road trip' and use the camper, I put all my stuff out on the Yakima.  Works very well.  Presently, I can mount 3 racebikes and 9 wheels, down out of the slipstream.  I can open the hatch with everything on there..it is a bit heavy, and of course, the struts are overpowered so I have a wooden prop to hold the hatch up with all the bikes on.

  I put some short sections of Westy curtain track onto the outside of the hatch to act as substitute rain gutters.  The 'towers' land in the short section of track and the regular clamps just go around the edge of the hatch.  The shape of the hatch makes slipping down under a big load impossible, because the hatch grow wider at the bottom..  An added benefit is you can visually check your load with the center mirror..
  Don Hanson