I bought a new high efficiency radiator from Ames performance for $529.00. It's manufactured by US Radiator in California. The Ames part number is p119amh. The US Radiator part number is 027290aanz. My old radiator which was not an original has tubes on 9/16" centers wit the drain plug on the right ( passenger side). The new radiator has tubes on 3/8" centers with the drain plug on the left side. According to USRadiator, the 3/8 will cool 20 percent better. Does any one know the correct location for the drain plug? Looks to me like it wouldn't matter.