I'm curious about what the last entry, xxx customer order, means. My build sheet for my '78 Z28 has it too. It seems to be fairly common. Does it mean that the car was ordered by the dealership per a customer's order? I wouldn't think that would be that common. My '78 Z28 I bought off the dealer's lot so if it does mean that it was special ordered for a customer they didn't want it after it came in.