In the past I've used a paint called POR-15 (Paint Over Rust) available here: POR-15: Professional Vehicle Restoration Products Pretty decent but not inexpensive stuff. They've got quite the lineup of products now.
Otherwise, just go down to a junkyard and pull the bed/tailgate from a truck that got smashed in the front.
Otherwise, just go down to a junkyard and pull the bed/tailgate from a truck that got smashed in the front.
