Stinky, aint it?
If I realy wanted to get rid of diesel odor I'd probably start by a good wipedown with mineral spirits (paint thinner) just to get rid of the diesel itself. Then a liberal dose of something like Fabreeze or Peggy Hall's bilge cleaner. (Oddly enough, available through the chandlery at this web site!) (Hey Phil, do I get any points for that one?) Patience will work too. Believe it or not, diesel does evaporate, and if you can get enough breeze going through the boat the odor will go away.