installing side scoops?

[tom'72]

I've got a standard bug with a Suby EJ20TT engine that's ready to be repainted after restoration in a few weeks.

I'm in doubt as to buy carbon fiber side scoops or not ( I used plexi NACA air ducts in the rear side window to cool the IC).

My question is: can I install these side scoops after the car is repainted (cut a hole in the rear quarter and glue the scoops over the painted surface), or what is the correct procedure to install these scoops?