Re: how do you solder a wire to the base plate?
edit: snowdog and lew beat me to it.
Use a dab of rosin flux paste on the surface before you solder the joint. Flux is the material that helps solder flow more easily.
Only rosin paste flux is suitable for audio work.
Acid-based flux (like that used for metal pipes) will cause the solder joint to corrode as electricity is passed through it.
This is the stuff most commonly available on electronics supply websites in the US, Kester NXG33.
(photo: kester.com)
A soldering gun is
only for big honking metal pieces like trem claws and base plates; inner plastic spacers (such as found inside pots, switches and the like) will melt.
If you try to use it on a strat superswitch or a push/pull pot, you'll wind up buying a replacement... I learned the hard way.
(photo: homedepot.com)
This is a 75-watt gun, which should be more than sufficient. If you use this on a regular basis (like building for friends and so on), you'll need refill tips.
Clean your tips (gun and pencil alike) with a wet sponge.
Practice before you commit, on scrap pieces. Get your technique down.
Trust my error-filled experience, chasing cold solder joints (which degrade easily, and create circuit problems) is a major PITA.