Heh, I can tell you from first hand experience frying the entire electrical system in a Mercury Tracer, that you do not want any wires running next to any metal edges. I zip tied a power wire from the battery to the windshield wiper motor to hold it down. It didn't LOOK sharp. Well, a year or so later it turned out it was. The entire wiring harness was melted into a big lump. You must run all wires through the firewall through big fat rubber grommets.