As typically the biggest concern is rust and associated big holes created by rust, a course in GMAW (Mig) or GTAW (Tig) welder would earn you a lot of mates. Welding thin material is a lesson in patience.
On the topic of patience, a lot of the resto work is actually easy if not mundane and I think you can just about do anything mechanically if you can read a manual or get advice from fellow enthusiasts. When I was younger I had no patience, try once, try 10 times then smash it with a big hammer from frustration. Now I can try 15 times