Sorry it has been some time but I think I either stretched it enough to push to power wire through with a tight fit or barely spliced the end to get some wiggle room. Mainly I remember trying not to have to cut it.
That's what I used. Also, the back speakers have a very low volume compared to the front, this is another reason why I wanted to run off the back speakers to run an amp to them, that and its easier and quicker. I thought maybe I would be missing a lot of bass running off the back speakers, not so much. Prob better off the front as people have mentioned (cause I did notice before I started the fronts have more bass) but the LC2i seems to be doing its job off the back speakers and have plenty of bass. So I added a Rockford Fosgate 2-channel amp for just the back speakers as the fronts are close and can be heard easily and have plenty of power. The back speakers rock and sound powerful now. Before, just fading to the back it was so low in volume and distorted when cranked, but the fronts sounded great cranked.. But I do have the LX and the radio is basic.For those wanting to do this without actually tapping the wires, this harness works for plug and play ability. Used it in my SI with no issues. I only tapped into the sub plug though.
https://www.amazon.com/gp/product/B0002BEPJY/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
