Unless you have ZERO automotive experience, Auto zone does you no good. You say you've built off road cars in the past. If so, then expanding on that background should be a cinch. I'm sure many teams could use volunteer help, especially in the weeks leading up to the big races.
You are living in a very convenient time for learning stuff. When I first started fabricating, I had to go to libraries and bury my nose in mechanical textbooks to further my knowledge. Lucky you there is a YouTube page for most anything you want to explore nowadays.
LEARN NUT AND BOLT TECH! That goes a long way when asking someone if they need help wrenching on a race car that they have tens or hundreds of thousands of dollars invested in, not to mention the investment they put forth for a given event. You'd be surprised how many people turn wrenches that have no business doing so. Aside from crashing, hardware failure has to be one of the biggest causes of DNF's. You'd be surprised how much clamping force is lost by using the same hardware just a second time.
Whatever it is you think you know, KNOW IT INTIMATELY. Don't learn a little bit about a lot of things. A "jack of all trades" knowledge base does you no good unless you're happy being a shop pick up guy or all around helper. Again, knowledge is power.