Bonnet Weight
The standard bonnet on a GTIR is 36lbs in weight (or Two and a half stone). I know this because I had to weight it for a client who wanted a G/F bonnet made. I then made a G/F bonnet that was 12lbs. but this was a single skin version that was for a racing car and had to use bonnet pins at the front.
On the subject of Kevlar if the bonnet has Kevlar it it it will be much stronger than just Carbon, as Carbon is strong but brittal. The best is a mixture of both (aramid) the yellow of the Kevlar will turn Gold in the sun.
If the bonnet is well made it will look fantastic in Carbon and or Cargon/Kelvlar mix.
This is not an advert for my work just a bit of advise about weights and materials. Hope you get the bonnets made would love to see one when they are complete, good luck.