Just bought stock Infinity Amp....questions

Ok my car has the wiring harness for the stock Infinity amp, and I was just surfing Ebay and found a guy selling a mint condition one and I nabbed it for like $30 shipped. My question is....can I just plug the thing in, or do I have to run some extra wires for something. Anybody done this? I searched but couldnt find anything usefull.

BTW, I replaced the shitty stock head unit with a Pioneer DEH-P7400, and I will be replacing the stock speakers with some Infinity Kappas. I just wanted a little extra juice for the new speakers. Any help is appreciated.

Ok well I did some researching on the internet since I couldnt find anything here...... From what I have read, you need to take out the stock amp when you put in an aftermarket head unit anyways just to get everything to work. Did anybody have to do this? I'm gonna be so pissed since I already paid for the thing without thinking it was gonna be a problem. I just knew that my car had all the wiring and everything, so shit why not buy this stock amp for a little more power. :banghead:

Anybody have to disconnect the stock amp after they put in an aftermarket deck?

buuuuuump

cmon guys I know somebody has experience with this

Mine was removed when i got an after market head unit. NOT saying you cant get it to work try it then let us know how it works!

UPDATE...

I got the amp, plugged the thing in, and nothing. Guess that solves the mystery. I tried it at low volumes and high, and noticed no difference when plugging it in and unplugging it, couldn't even tell if it made the tweeters in the dash work or not, there was no difference.

the stock head unit is made just for the stock amp. when you change to a aftermarket head unit and use a custom wiring harness they usually only hook up power, ground, speakers, not amp turn on lead wire which is usually blue with a white stripe. That is the color of the wire coming of aftermarket head unit. You will have to find where to plug this in to factory harness. Also, your stock speakers are most likely 8 ohm. Remember this when upgrading to different speakers. BUT, if you decide to not use stock amp, the common upgrade is to 4 ohm speakers.