Installing this unit was the first time I had ever done any soldering before. I decided to use an old PC card I had lying around to do some practice runs to get a better feel for how much solder to use and how everything would work . The contact point you have to solder the wire to is small, but keep your hand steady and you will be fine. Just position the wire on the contact point, heat the wire with the gun, and then add some solder. I only used the equivalent of 1 drop and mine has stayed connected with no issues (even with a high milage stock suspension and Michigan roads).
Give yourself enough time, have a small tip soldering iron, and practice first. You should be fine.