Here is what I do (fresh water, but I would assume it would work for salt
water):

Coat the bulb contacts and base with wheel bearing grease. The contacts
will still touch through the grease, and the grease keeps the water from
getting to the contacts and corroding them. Has worked for years.

But, if you really want to go High Tech, get the LED bulbs. You will feel
better, but your wallet will be lighter.

"Doug Kanter" wrote in message
...
Sorry about posting a topic related to boats, but I seem to recall a
discussion last summer wherein some of you regulars (or "regliars", as GWB
would say) had recently installed waterproof and/or LED trailer lights.
I'm
interested in status reports on those lights, especially if they were
purchased from West Marine or BoatUS. I'm finally fed up with removing the
corrosion from the bulb contacts with a Dremel every damned spring.