Those fiberglass bumpers are for sure hit and miss. Even if you spring for the genuine Techart kit, there was still fitment issues with 2 different kits we installed. The bumpers in the Techart kit fit great but, the side skirts were a horrible fit. They had to modified twice. The full 996 Turbo kit we installed was $20K from Techart. Honestly, for a price like that I expected it to be Poly and fit straight out of the box. Really disappointing when you piss away that much cash to have to modify brand new pieces. The car does look good...now.
Before:
After:
I had thought about buying aftermarket fiberglass skirts at one point but, after those episodes at work I'm on the hunt for Aero kit skirts.