Replacing strip lights on 2004 Symbol

I need to replace a couple of fluorescent tubes in my 2004 Symbol, but I just can't see how to get the clear plastic covers off. I've tried a screwdriver at the edge but don't want to exert too much pressure for fear of breaking them or ripping the headlining.
Anyone out there had experience of replacing these strips? they are the long rectangular type. I will grateful for any advice.
Many thanks, Mike.

Mike,
I too had the same concerns when first removing one of my lamp covers.
I use a home made tool much like a right angled screwdriver with a flat blade. I insert this flat blade under the clear plastic lamp lens at one end where you will see a little indent. Gently pull the cover outwards very slightly by moving the tool in towards the van body. The lamp cover will then move over the pip that is holding it and become free at that end. You may have to repeat this at the other end.
I made the tool out of a small piece of metal from my scrap bin and keep it in the van so that I can change a tube when away from home. I carry a spare tube.
One thing I found is that different tubes have a slightly different light colour and so it is often better to fit similar tubes to one lamp if this annoys you. {presuming that you have 2 tubes per lamp}

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