One of the bulbs in a double light fitting isn't working. I can't figure out how to get into it. It's a 97 Triton - photo of fitting here.IMG_20200726_170800944_HDR~2.jpg - Bild entfernt (keine Rechte) Anyone who's done this before would appreciate some guidance.
Many thanks.

Finally got round to tackling this. Not too difficult and I add this to help anyone who needs to replace a bulb in this old style fitting.

Put a blade or screwdriver into the gap beside the outer plastic ring. Prise the light unit downwards. It will pop out. It's held in place by a lug in slot as highlighted in the photo. To replace it align the lug and slot and push it upwards until it clicks. IMG_20210615_122848633~2_copy_1024x1365.jpg - Bild entfernt (keine Rechte)