2.5 Stick

Will take pics. Thnks for the HU to H/K amp info.

I'm going to get the dash kit and replace the head unit in my '09 2.5i MT. I'm going to use a new Pioneer/Alpine/or Kenwood flip out. I'm not going to get a 4 Channel amp, instead I will use the flip out's built in amp and set the Hi-Pass Filter so I don't get bass to my door speakers. I won't change the Harman Kardon interior speakers. I will connect a Kicker Mono Class-D amp to the sub-out on the head unit and that amp will connect to my Kicker L7 single Sub. My question is, the harness that they are selling @ Crutchfield, will it by pass the Harman Kardon amp under my pass. seat? This was the set up I had on my Mazda CX-7, but with a different head unit that had built-in High Pass Filters. The stock H/K system sounds good for most modern music, but last wk I started noticing distortion from OEM HK sub already. I know how to install myself...I upgraded the new CX-7 my self, that dash kit was easy to install, hopefully same for new Legacy? So, which wire harness will be ideal for my set-up?