Plastic tanked radiator....

Part of the purpose of the plastic tanks is to electrically insulate the AL rad core from the chassis. Unlike brass rads, where the electrolytic corrosion concentrates in the iron block, an AL rad gets the brunt of the natural electrolytic corrosion, and breaking the electrical connection to the chassis helps reduce that AL rad corrision. So, for a road truck, I'd keep the stock plastic tanks and insulating mounts.