I need a map light bulb for a goose neck map light. I took the old one out and it has 1816 12V 4W on the side. The ones I have found do not fit they have a large bulb and won't fit in the map light. Am I correct that you just drop the bulb down in the hole and put the cap back on the light.
The 1816 bulb (according to the internet) has a bayonet base. You need to push and turn the bulb.
I'd look into replacing it with an LED.
A quick Google search turned up a number of 1816 LED replacement. Here is one:
1816 LED - industrialleds.com (http://industrialleds.com/index.php?main_page=product_info&cPath=13&products_id=77)
And it is available in colors. Red might be a good choice if you don't want white.