just replaced the older kenwood from 2003 on my express. Did not need to re wire but did need to splice the wires for speakers and power. Grady was nice and used solid wiring harnesses, so it was not a huge challenge to do the splicing, as the wire harness was removable, and I could do the splicing and heat shrink at home, where I did not have to contort. As mentioned above, I needed to make a faceplace as the units were different sizes.