Forgive me all for I have sinned.........Last weekend I fitted a stereo into my 2011 Plus 4.
A Sony mech less head unit ( Bluetooth, Pandora, USB) no CD, fitted straight into the existing cavity. The wiring harness plugged straight in ! With that, I installed a Kicker 2 channel amplifier which I mounted in the passenger footwell ceiling (well hidden). 4.00" Alpine two way speakers fitted beautifully into the footwell cavities with a little trimming of the carpet. There was some additional wiring which include better speaker cables and a power cable from the battery direct to the amp.
In all, I am very happy with the installation and it cranks!
Also note that the head unit comes with a remote so I can control the music without wrenching my neck. Can also use my IPhone
