The rear LED lights are aftermarket and I haven't told my insurance about them

Now, do I play dumb and say they were on the car when I bought it or do I tell them about the lights.
It's going to be an insurance job and she has already admitted liability to her insurance.
Forgot all about my voluntary £400 excess as well which was another kick in the balls

I've always had a large excess to bring down the premium and I've never had to pay it (18 years no claims upto now touch wood)