Looks like I underestimated by around $2,000. As the auction for Daryl Hannah's matte black El Camino was ending yesterday
, I guessed the bidding would reach $13,500. Since the car was a.) reconfigured to make it more biodiesel friendly and b.) owned and driven by Hannah herself for quite a while, it seemed that a jump of $4,000 in the last few hours of the auction was reasonable. Instead, the final bid was $15,600, and it looks like that beat Hannah's reserve price.
The car was bought by someone who uses the eBay handle bhagwano, and we wish him or her the best of luck with this black beauty.