MOT handbook states the following:
The only light visible from the front of the vechicle must be pure white (no colouration of the lenses) or amber in the case of the indicators.
The only colour visible from the sides should be amber
The only colour visible from the rear should be red, or in the case of the indicators, amber. there was a loophole in the law that allowed you to run with no reverse light but I believe that has been closed now.
As for nitrous it MUST be declared to your insurance company (if its not declared your insurance is invalid and as such you are driving without insurance, which then renders your road tax invalid), you must also display (preferable on the front and rear number plates) and orange triangle with 'compressed gas'. there is also another code you need to display which i dont have to hand (this is so the emergancy services know whats in your car when its burning). Both these are regardless if the system is plumbed in or not, as by having a tank of NO2 in your boot your impling you have intent to use it. The only way I would think you can get round this is by having an empty tank.
hope that helps.
Under car neons
thing is u can see the bulbs directly which is what that relates too...which is y u can get away with the reflection...unless that loopholes been closed now tooMOT handbook states the following:
The only light visible from the front of the vechicle must be pure white (no colouration of the lenses) or amber in the case of the indicators.
The only colour visible from the sides should be amber
The only colour visible from the rear should be red, or in the case of the indicators, amber. there was a loophole in the law that allowed you to run with no reverse light but I believe that has been closed now.
the idea behind it is...
if ya car was held over a bottomless pit would u see the lights...as far as neons go if the answer is yes..they're illegal.....if no..your safe
as i say tho..could of changed now