I'm using the factory radio now. The JVC head unit was temporarily hooked up while laying in the seat. It gave the amps better, cleaner sound with lower bass frequencies, so I ordered an installation kit for it. This little Clarion EQ is awesome. The sub level control is the icing on the cake. I did nopt want to slit the carpet to run the wires underneath, so I will have to get used to this look. There was no other practical location to mount it where I could easily reach it, so I made the little stand out of MDF and found some paint close to the color of the carpet. The seats look different colors in the photo-how weird. The wires digitally removed in Photoshop. That looks better! The Alpine powers the rear speakers and the Blau runs the 2 MTX 10s. The original trunk carpet would not have allowed the amps to be mounted due to the shape it's molded in, so I had to cut it out. 2 pieces of plywood were mounted under amps and black carpet. The trunk mess. When I'm finish running the cables underneath the carpet, I can put the spare tire back up in the right side of the "shelf". Future bass plans are 1 Alpine Type R 10" and Alpine MRP-M500. And the Blau will power the front speakers. And after all these years, they finally started putting tachs in the Grand Marquis in 2006-l love it! And here's the car in front of the Amtrak station in McComb, MS.