hello, I am still new to this l67 scene. so far on my 99 gtp i have done a complete tuneup with 1 step colder plugs, pacesetter headers (no cat), wizard intake, and a ported supercharger. i was thinking getting a boxed tune and a 3.4" pulley and being done with it. but meth injection kits look good and not that expensive. but reviews on here say they are a waste of money (or they were a few years ago) So i guess my questions are, is the 3.4" and be done the way to go, or could i go to a 3.3 with my current mods? and is meth worth it?

thanks for your time
Bruce