Can you do bracket fabrication? If so then get a Speedway RACE catalog, not their street rod catalog, and look up radiators. The sell their own brand of double row 1" tube aluminum radiator that will cool any street engine. You buy them with measurement as to the size you need. Cost $110 brand new. They work just fine in a vertical application but you have to move the filler neck if you stand them up. They also offer an inline filler that fits the upper hose so you can just plug the original filler with a high pressure cap and fill through the one in the top hose. Also have mounting brackets and pads but I've never used them since they are for horizontal mounting.

Evan