Jim and Sniper........very good points. I was thinking of slightly tilting the radiator, but for space reasons. The bleeding of air thing makes perfect sense, and I will have a radiator shop add a bleeder to the top tank. Honda's have a bleeder on top of the engine, and after working on one if you don't open it until you get no air bubbles, it will overheat. (Don't ask how I know........ )

The 19 x 31 size is perfect and in fact I have 40 inches width back there to work with. With a 16 inch SPAL fan or maybe two 14 inchers I should have no problem cooling it. The bed cover is punched with 224 louvers and I plan on punching more holes in the tailgate too, so air should be able to move through well.

Sniper, you have given me an excellent idea. I was thinking steel tubing for the pipes going to the rear, but alumimum makes so much more sense. I bet I can pick up some 1.5 and 1.75 locally and it should also dissipate heat better than steel would. Thanks for mentioning that.

Don