Originally Posted by Blazenlink
The only RCAs connected are the 2 sub ones. The kit I have only had 2 RCAs. What small 8 pin connector are you talking about?
In 2013/14 with the Shaker system (not Pro), the front,rear and subwoofer speakers are all driven from one amplifier. So, the Sub RCAs are not used. The 8 pin plug I refer to is the one that the Sub RCAs go to on the car side. There are three plugs that can go to your car - 24 pin, 16 pin and 8 pin. The 8 pin connector is for REAR subs in Shaker Pro.
As for connecting to the amplifier, connecting speaker outputs from the radio to the inputs of the amplifier (using the MUS1 T-Harness) will work but will overdrive the amp, resulting in very loud sound at very low volume level in the radio, as well as some floor noise.
You can eliminate these issues, but cutting a pair of RCAs in half and connecting them to the white, gray, green and violet speaker wires of the MUS1 T-harness. The center conductors are positive and the shield are the negative.
Then plug these into the Front and Rear RCA outs of your deck. If your car has Sync and Shaker, then both the SUB IN and AUX in RCAs in the MUS1 t-harness are not used so you could just cut those off and use them for the modification.
Hope this is clear/helpful.