I have the same question on a 1984 Mk1. About to go up with my new mast-mate climbing system.

THE BULB in the ancor light should be a festoon bulb. I changed all mine to LED bulbs they draw 1/3 of the voltage as the old stlye and now they make them to fit just about every light fixture out there

As for your deck light hard telling I CHANGED mine to a forspar light the old one was beat so instead of fighting with it I just changed the complete unit.

Sorry I could not be more help

Thanks, Ed. Good idea.

Sorry, I mean Jeff.

The AquaSignal bulbs are festoons but they are dimpled ends, not pointed. I believe they are 44 mm, at least the box my replacements came in says that.

BUT - I just put a new steaming/deck light on because the old one was sad and unreliable. I was pretty dismayed to see that this new genuine AquaSignal unit had a pointed end festoon in the steaming light, not dimpled, therefore none of my expensive LEDs will fit it. Fortunately, it only runs when the engine is on anyway, but still. I hate when the manufacturers do that.

West Marine carries the pointy end LED Festoon and the dimpled end festoon bulbs in LED,they are made by Dr LED.
That is what I have in all Running lights, steaming lights,and anchor light at mast head now

First you need to identify the make of your fitting. Then you can look for the bulbs (of your choice).

The West Marine catalog has a good listing of the few steaming/deck light fixtures, as well as info on the correct basic replacement bulbs. You'll have to do some more leg work to find the LED replacements.

AFIK, LED for a steaming light isn't warrnated, 'cuz your engine would be on anyway, and the LED could (maybe) be more problematic than a standard lamp.

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