Suspect you would undo the chrome nut in centre of light cover ??

I would also presume the center nut. You probably need to give it a good spray with some inox or something and let it soak. I would imagine its corroded a bit.

Tap the chrome nut 3 times and wait 10 seconds it should open!

Bushdog said..
It is the centre nut. Back of the nut is stepped and the 'glass' has a 1cm hole in it. Use the inox or wd40. Side lever is the switch. You can replace the globe with a small LED. Don't do it up too tight, they always seem to self tighten. I've used multigrips to open them a couple of times, the thread seems pretty strong. The plastic lens is the weak bit.

Thanks Bushdog.
Now i know it is definately the centre nut i will spray and get some vice grips to it.
Cheers.

Go to Whitworth's and buy a new led light fitting, then hit the old one with a hammer. Problem solved and will never need to change the lamp again, plus more energy efficient.

On the topic of replacing traditional interior lights with LED.. Is there any advice for changing this type of fluorescent? cabin light for an LED alternative? Can the bulb be swapped out or is it easier to replace whole unit? Thanks, Jd

jdol said..
On the topic of replacing traditional interior lights with LED.. Is there any advice for changing this type of fluorescent? cabin light for an LED alternative? Can the bulb be swapped out or is it easier to replace whole unit? Thanks, Jd

The fluorescent tube isn't a bulb, it's exactly what its name says it is, a tube of glass with fluorescent gas inside, when electricity passes through the tube it excites the gas and creates light, so the answer to your question is no, you can not simply replace the tube with a LED, you'll have to replace the old fluorescent unit with a new LED unit, sorry for the bad news, but here's some good news, you should be able to plug the new LED unit into the old wiring and when your done you should have better lighting for less energy use.