Hi on one of my cars brought the cable down from the trunk along the door frame and ran cables along the drivers side floor right along the heater channel. I covered the cables in the black corrigated tubing and used black Ty Wraps to fasten to the heater channel. I did it on the drivers side because I am aware it is there and never have a problem hitting it with my foot. After always having problems with the inside floor mounted brake line rusting out, I also ran a new line several inches above the original line. This prevents moisture from the floor rusting it alway. Any time I replace any steel on the car I replace it with stainless steel. Check out my site and then go to photos of my car and you can see the stainless floors.
http://home.att.net/~nextgen
Joe Cali