Jerry, this radiator is an odd shape. It conforms exactly to the shape of the grille shell, so the bottom tank is roughly a triangle 15" wide x 9" high x 3" thick. When I was building the car, I took it to a custom radiator shop and they told me they couldn't do it and recommended the external cooler. I'm going to have to give this some more thought.

Lynn, my coupe is channelled, and there isn't much room under the car.

I don't want to hijack parkwood's thread any longer, so if I have other questions or comments, I'll start a new thread. Thanks to all of you for your thoughts and advice.