1999 Gs400 Amp Locaion And Installation

[Ali]

Hi guys this is my first post on this forum website and I am a newbie to the Lexus cars because I had a Nissan Maxima before this. Ok my first question is that where is the amp located in a 1999 GS400? I have the stock stereo installed and I don’t want to change it. The stereo that I have in my car is the premium audio system by Lexus and I don’t have the Nakamichi system in it. The second question is that how am I suppose to power on my amp when I install my system without putting in an on/off switch for the amp? Is there any way I can tap in a wire on the stock car amp which will turn on the amp when I turn on the stereo? Also if that is possible which color will the wire be?

I have two 12 inch Kicker L7’s with a Hifonics Brutus 1600 watt mono amp

Thank You