MOT - to fail or not to fail?

[DVR80]

my offside rear light cluster has broken, nothing major but some of the plastic is missing across the bottom of the cluster.
i realise this will eventually cuase blown bulbs but in the mean time, is it likely to fail the MOT bearing in mind they are still in perfect working order and the missing piece of plastic is not big enough or near enough to the middle to affect the visual aspect.

[ini]

I am not sure, but i think the old rules still apply.

No white light must be visible from the rear of the vehicle, if it is, a bit of coloured tape should allow it to pass.

[Dave83polo]

also make sure there are no jagged edges showing, if so tape over them, if you can catch yourself or it could cause harm i could fail.

[discobarry]

Yes so long as there aren't sharp edges or it isn't showing white light and the lights are working fine then you shouldn't have many problems unless the tape you use takes more than 50% of the emitted light.

Why don't you just fix it though?