Steelcog

So further information. I realised once the black plastic slide clips are off one also has to flick off the 4x stainless clips from inside of the wagon door - I used an O ring picker. Light gently pushes out after that. New light needs these clips refitted before clicking into place.

Having exact same problem myself. Seems like they never fail until physically broken. Have everything disassembled and slide clips off but unable to release light assy. Will keep prying 😬