I think he means the IMRC plates. I would leave them on. Removing them will kill the torque on your car. They don't weight much either, so don't worry about the weight of those. Cutting weight is stupid IMO because you are taking off luxury of the Cobra. One time I removed my sway bar, passenger seat, back seat, console, glove box, trunk stuff, spoiler, wipers...etc.....
I ran NO better. MPH, E/T, 60ft...nothing got better. It just wasted 2 hours of my life. You would have to cut 500-1000lbs to notice a difference. Even with a passenger in my car, my car didn't slow down at the track...and his weight at the time was about 200lbs.