We spliced in extra wire to compensate for the longer distance on my car. I haven't had any problems with it at all. I would rather have them be soddered instead of butt-spliced, so that might happen next time I jack the car up and work on it.
Be careful though, to connect the correct wires when reconnecting them. Mine had 3 different wires; 2 white and 1 black. We tied small zip ties around 1 of the white wires so we were sure we were connecting the proper ones.
Just be sure to get like 9 extra feet of wire somewhere (should be plenty to reroute things where you want them). Maybe get more, as I'm not sure just how much we used originally.