Hatch/Trunk Problems

ltp

I was at the dealer today and noticed that the Nismo Z has a couple transparent rubber pieces about 1/4" thick glued to the opposite side of the car where the springs hits. I believe due to the extra weight of the Nismo spoiler, Nissan adds these to Nismo cars to prevent the problem even with the fixed springs.
This is similar to adding pennies method which gives more pressure to the springs.
I prefer the rubber way or add rubber washers to the springs instead of pennies since pennies can rattle and add more noise to the already noisy Z.