Mounting roof racks on 1990 Dodge Xplorer Van

I did that once on my 1985 GMC camper van, in order to carry 2 canoes up top. I just used a pair of old fashioned gutter rail racks. I fabricated a piece of aluminum into the shape of a gutter(about a foot long), with about a 2" flange on top of it. I drilled through the made up gutter and the F/G top, inserted through bolts and made a backing plate of aluminum for the inside. It's a 2 person job to get it all assembled. I then drilled some more holes into the vans raingutter and installed some carabiners through the holes. This was for tying down my 2 canoes, as you don't want to rely on just the F/G, but rather the vans' steel body. It worked great! Sorry, no pics.