I agree with Hyla about the head lights.

Re ceiling: A ship which is going to carry foodstuffs, like grain, in bulk, which is poured/loaded directly, and with no packaging of any kind, into the hold of a ship, generally has to be protected from contamination, moisture and rats by a ceiling. There are ship ceilers, who build a ceiling, or wooden inner liner, in the holds, and it covers the bottom and walls (bulkheads) of the hold. Hence, the bottom, which a landlubber would call a floor, is a ceiling! There's glory for you.