A big part of the answer you are looking for depends on where you plan to live when you graduate. If you live in a smaller town, the jobs are scarce. If you live in a large city, there are restoration shops you could work in or open your own. The population supplies the demand. I live in a town with official population around 85000, and there are only 2 or 3 shops that do restorations. Go to Dallas and you will find many shops, some specializing in certain makes like Mustangs. The West Coast is well known for customizing/restoration businesses.
You are thinking in the right direction, go to college and learn the skills you need so that when you get out you can get a good job doing what you like best. Try to make some contacts in your area, find out what shops exhist and talk to the owners, let them know what you are planning, get them to let you hang out and see how they do things, keep in touch and when you graduate you could possibly get hired by them.
Everything I know about working on cars I learned the hard way, by doing it. I have made a lot of mistakes and had to start over on a few things, had I had some training that wouldn't have happened. My friend and I have been working on cars since high school (I won't say how long ago that was) but we don't have the time or space to work a lot, just in my 2 car garage, so the process is slow, but we do good work.
Good luck to you, I hope you make it BIG!
