Dash Shaking! Help

Up until today, my car would go up to 120mph Before the Carbon fiber hood would start shaking.
I haven't been in a major hurry to get it straightened out because I don't do 120 a lot.
So today a friend and I changed the idler pulley the supercharger pulley and put a Steeda cold air intake on my 2008 4.6 L Stage 3 Roush.
I bought the kit from Brenspeed.
Everything came off and everything went on fine no problems.
After I loaded the tune, started it up everything ran fine looks fine etc.
I get it out on the road after it's warmed up I bring it up to 90 miles an hour my whole dash mainly the top starts shaking like crazy!! Every single time, it starts very mildly a little over 80 by the time you hit 90 it's shaking really good and the faster you go the faster it shakes, vibrates like crazy.
My friend left before I thought to have him rev the car while I looked at the motor and the pulleys. but I never thought it could possibly be the new pulleys because just looking at them at an idle they're spinning fine and true.
The steering wheel feels fine, and I have not hit any potholes or anything since the other day of going 120 miles an hour and everything is fine except for the hood.
Anybody else ever have this problem?

Mystery Solved.
The cause of the dash vibration was caused by a loose chin spoiler, quite interesting to me at least how things can transfer through a car from one spot to another.