The wire for the SWI-JACK is going to be under your driver side dash. You will pull the leather panel, then the plastic panel has two bolts and it comes out. There are two harnesses, I believe the wire you want is in the right harness. Be sure to check your colors carefully. Also read the programming instructions carefully. First time I programmed it I programmed volume up to be not pressing any button. That was almost bad.
I was able to dremel my tweeter pods out to fit new tweeters, although later ended up building the pods out with bondo to fit the tweeters better.
Do you have a monsoon or bose system factory? If so, your going to want to bypass the factory amp, and it would probably be best to have a separate crossover network. The factory amp has 4 inputs, and 8 outputs I believe as far as speaker wires go. Front left and right input, and rear left and right input. Crosses over in the amp, then sent out to each individual speaker. You could bypass the amp and run the inputs into a crossover that splits the output to a high and low for tweeter and driver for the fronts, and then for the rears power the rear door speakers off the rear channels, and leave out the 6x9'* replacing them with a subwoofer. This is just my suggestion, there are other ways to do it. It is also dependent on your system being layed out like I think it is.
COTY - 2012
Tom - 03' Bonneville SSEi', 00' Sierra SLE, 1980 Goldwing GL1100 Interstate