AS Topaz Down lighter bulb replacement

Hi Everyone,
Probably a stupid question but thought I would ask before attempting this and making a mistake. I have a 1994 VW T4 AS Topaz and one of the interior down lighter light bulbs has blown. I have briefly tried to see how to remove it but can’t find how. Any advice on how to do this? Many thanks for looking.
M

It will help to post a photo of it, but typically the small "eyeball" type halogen downlighters have a retaining ring around the outside which twists off anticlockwise to allow the clear cover to drop away.

If the existing bulbs are halogen, you will save a significant amount of battery power if you convert them to LED.

Thanks Roopert,
I’ll take a photo next time I am in the van (in storage). It is the small “eyeball” halogen downlighters so I will try unscrewing the black retaining ring to get at the bulb. Thanks also for the tip about changing to LED from halogen.
M