If you haven't done it yet, might also want to make sure you have a copy of the listing on eBay stating what all the parts were supposed to be, If the dealership is at all concerned with protecting their reputation, a copy of this and the photos and doucumentation from the machine shop that inspected the engine should get you a refund, or at least the money required by your machinist to make the engine match the advertised specs.....

PS---Don't forget using the Better Business Bureau where the dealership is located for a little added leverage !!!!