That's a great kit. Installed one on mine last year. It worked out great. In fact I've got another one in my garage awaiting my decision to tear into my GTO and start it's rewiring. Sooner or later I'll start.
Just take your time and read your instructions. I'd suggest running all of your wires to where you'll want them before terminating them. That way you can change your mind on the routing without having too much or not enough wire...