[3dplane]

I'm trying to make rear wheel skirts for my car but there is a problem that the body of my car curves in very agressively from way above center line of the wheels,therfore the wheels are sticking out so I could only put a little hitler moustache on for wheel skirt as it is, which would look silly and possibly not do any good for aero.

So I decided to bring the body line out at least close to flush with the wheels by creating these...I don't know what to call them wheel air deflectors/fairings?

I want a descrete look so they are going to be painted to the color of my car and clear coated.
Since they are made out of styrofoam,before I can apply any Bondo or primer I will have to either tape over the entire foam surface or (testing now) use spray adhesive and wrap it in aluminium foil so the foam does not melt away due to the chemicals.

My question is: Should I fibre glass over the fairings (over the tape or alu foil)?

And then Bondo,sand,primer etc. Or just skip the fibre glass and Bondo over the tape or foil and continue paint prepping.

What will I gain fibre glassing them? Besides that it will take a kick or a rock better than without it.

Easier mounting due to better structural strenght?

Please share your experience/opinion and give me a reason to go either way!
I just don't want to mess with the glass unless there is a good reason.

In the pictures you will see the piece trailing the tire is already wrapped in alu foil so it is hard to see. The piece in front of the tire is bare foam. And in the car pics the silver part is held up to the car by a piece of scrap foam against the ground,don't let that bother you : )

Thanks!
Barna