Hook the serrated eyelet up to the power post on the back of the alternator. Tun the wire & conduit to the back of the car, keep it away from the driveshaft, suspension parts and exhaust. Zip-tie it to the frame where you can (I zip-tied mine every 24" or so). Unplug the factory weatherpak connectors behind the gas tank and plug the ones in the hotwire kit in between the two (they'll only attach one way), then attach the ground strap (with the clip on the end) to the seam of the gas tank, making sure it's really secure for a good ground.
That's how mine went together, I had the same problem as you, I got the kit from the previous owner, but it had no directions. I think it was the Casper's kit but can't be sure.
Steve