I'm not sure how they ran the coolant from the engine to the radiator on the DeTomaso Panteras, but stainless steel pipe could be a good (but not too cheap) way to span most of your front-to-rear distance with a pretty tough and corrosion resistant conduit. The installation would determine where to put "S" hoses as strain and heat expansion/contraction relievers and other short hose sections to point the coolant where it had to go. If 304 stainless exhaust tubing would work, it's less than 10 bucks a foot for 2-inch 16 ga (0.065 wall) tube, and I'd like 304 a lot better than copper. Galvanic potential issues might make something like a few Caddy Northstar "pills" a decent idea, but this is all back of the napkin rambling on my part.
Are you going to try getting direct airflow when the vehicle is moving, or do you want to do all of that with electric fans?