Pretty sure is is 3/16". You can do one of many things, though.
1. Pick up a package of 3/4" long self tapping sheet metal screws (about $1.00 at any hardware store) and not worry about drilling. Take one of the factory screws from the factory speaker and find some that are the same size or a little bigger. (i recomend this option, personally)
2. Get your drill bits out and find one that fits lossely inside the existing holes (don't want teh hole to be too big)
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
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