Tires: Tax credit for new and used tires

Our truck dealership sells both new and used vehicles. We understand that, effective Jan. 1, 1998, a credit is available against the tax due on a taxable truck, in the amount of the tax imposed on the tires under Internal Revenue Code Section 4071. As a dealer, what steps, if any, must we take in order to claim the credit? Can we take the credit for the vehicles we sell with used tires?