Third brake light removal UK Mk1

Removed the 2 gold nuts, but the light will only slide half way up the studs. I don't want to force it in case I break it. Is there another clip anywhere ?

Roadster Robbie replied

There is a tag on the brake light. look in the hole where the light will come out of. The tag is red plastic like the rest of the lamp so quite hard to see. You'll probably need a screw driver to release it.