Stereo & Electronics - shift light help

hey guys, i want to put in a shift light.
)Proform Adjustable RPM Shift Lights). it says i do not need a tach or somthing. im a little confused on were to connect it. I didnt purchase it yet, but im looking for a shift light and use my stock tach. What should i do, and were do i connect it

Raptor has installation info along with PIN assignments to connect their shift light.

http://www.raptorperformance.com/Installations/Chevrolet/Camaro/camaro.htm

I've got the Raptor w/blue LED's and I mounted it in my driver's side defroster vent. I bought a grommet and it fit right in and looks GREAT and works GREAT!

what size grommet, id and od, did you use. Just got mine in and getting ready to install. thanks

I don't even remember...I just went to Lowe's or Home Depot and took the light with me and found one that fit the shift light and then I measured the vent hole to see what size I needed for the O.D.