'99 installing tweeters on factory stereo

None of the wires behind my factory stereo are labeled- I need to pinpoint the right wire to cut for my tweeters. I want to make sure I'm cutting the right ones. I need the front speaker wires to be split to connect to my tweets.

goodluck.... why dont you use a aftermarket radio?

well, right now, aftermarket stereo isnt in my budget- and i have the tweets now, so i want em in now, ya know. so in order to figure out which wire went where (thanks chevy for not labeling) i took off both door panels to find out myself. i then wired the tweeters from the door panel. took 3 hours, but i got em. <:)