I couldn't wait to take my rack off the old truck after camping, it seamed to create an anoying howling wind noise without the canoe on it.
I used the Yakima Q-towers with the Q58 clips. It's a real tight fit and looks like the door is going to hit the clip but it works. Also the roof sheet metal seams really thin and I'm always affraid to over tighten the rack, maybe this system would spread the load better.
Already have a small dent from a branch catching on the tower and then rubing down onto the roof offroading. I use it for the conoe and tie the bow and stern down for extra support.
If I designed my own I would probably go with a window guard/rack that goes up from the bed to work as the back rack (and/or attach wind deflector if desired), and a front mount like above but a headlight bar with a small square reciever pointed up. The other trick is figuring out how to get the toys up that high and when camping. So may still need the front bar, and thinking of maybe a removable, shorter/adjustable, cross bar mid bed so I could run the conoe up from back without assistance.
Eric