Interesting. Now you got me thinking. How about 2x BMW K1200 radiators with fans in the fenders along with a center radiator? The sizes look pretty good and along with the center rad it could possibly work.
04 05 06 07 BMW K1200LT Radiators w Hoses Fans Left Right Side | eBay
BigSmoothlee - currently I have the 4 cyl 912 motor in it. Its an industrial motor with towards marine application (originally for the Porsche Boat in 60's). It has like 40hp and runs like an early vw bug.