New Touchscreen
In order to make our factory Blaupunkt head unit a touchscreen, I took a Kenwood KOS-L702 7-inch monitor apart, separating the touchscreen layer and overlaid it onto the factory screen. This is possible by extending the wires to the brain of the monitor to the touch membrane. Removing the factory radio and monitor from the bezel allows you to slide the membrane in front of the monitor. The bezel has a plastic trim; when you notch the corners out, the membrane fits securely into the bezel.
The only problem with this install is that Kenwood doesn't make a video touchscreen splitter. Adding the Nav-TV piece forces you to use a Kenwood KOS-CV100 to change the video signal into a composite signal. The CV100 takes the touchscreen monitor port where the screen would usually be connected. To solve this I simply cut the CV100 cable and the touchscreen monitor cable in half and soldered them together. This makes the video signal a little low but the RGB box (that Nav-TV provides) has a positive and negative adjustment on the side. Adjusting the positive will increase your video signal. The factory deck has a front and rear output you could use for aftermarket amps. The front and rear outputs are labeled on the top of the factory head unit and are visible when pulled out. Cutting the ends off of one side of the RCAs and soldering them to the labeled wires will give you output you can use for your amps.

Now you can add whatever amplifier you choose. In this particular install, I replaced the front component set with 4" component set speakers and the rears with 5.25" speakers. To handle the low end, I added two 10" speakers in the trunk.
This gives you a clean install without having to lose the factory head unit. The touchscreen inlay made the factory deck easier to use and brought back the class that you would expect from a Maserati.