Hypoid previously posted:
"Read up on any sanctioning body's (NASCAR, NHRA, IHRA, etc...) safety requirements. You won't find some high school kid with a MIG welder making these cages."
You might be surprised with that. Obviously with NASCAR and such there are a lot or regulations, but for the feeder series and dirt track stuff, as well as the more amature level Rally and Offroad series, a lot of that stuff is done by shade tree mechanics with a relatively cheap bender and a MIG welder using Mild Steel. As long as you follow the rules and use the right materials, people can do pretty well on their own (including High School kids)...