Utility knife is your friend.

Just slit the bottom of the factory cover along the threaded line. It will just peel off like wrapping paper.

2006 Pontiac G6 3900SFI GTP Coupe CAI, Stainless Cat Back, Vector Tune, Strut Brace, Eibach Pro Kit, Custom Made Projector Headlights, 4300K, 20% Tint Former Owner- 2000 "Stryped" CSVT CEG Dragon Run- Oct 13-15