Help with lights on Bateson Trailers

[YH31]

I need to change the brake light bulb on Bateson Deauville trailer. It’s a newer model with the light cover that’s fastened on with screws. I’ve taken the light cover off but the brake bulb sits in a recess at the bottom of the internal fitting. I can’t see how you get the bulb out and don’t want to start using brute force on the wrong bits. I’m probably being really stupid but can anyone help. Thanks.

 

[DirectorFury]

Can you get at it from the back of the light assembly?

 

[YH31]

It doesn’t look obvious that you can but I think I’ll just have to be brave and give it a good tug