I've been involved in rally for over 30 years wearing every hat and sitting in every seat you can. Rally in America goes through ebbs, but right now we have two different sanctioning bodies. Now, to an off road racer, this is status quo, but for a long time rally was SCCA. Then Rally America came along, SCCA went away, and some people who did not cotton to the ways of Rally America started their own series with USAC. Then it bounced around for a while, but Rally America (RA) was the recognized playground of the factory teams. Then RA was sold, that didn't go well. Then another group formed the ARA, which is now the recognized playground of the big dollar teams. But ARA, which started with such promise, just flopped back over to control from the original group from RA. Customer Service has suffered since.
The SXS rally racers set some amazing times, they look fast, and everyone seems to be having fun. But, and I cannot stress this enough, double check the safety regulations on your build! Rally Idaho had over 20 entered, then ARA changed the rollcage rules after everyone powder coated their rollcages. Idaho lost a lot of entries. The Idaho organizers are so great at what they do, it was massively unfair what happened costing them all those entries. But, if the event is run under NASA sanction, then everyone should be fine.
Having run Gorman a few dozen times I can say you will have a ball, it is well worth going. Great organizers, great roads, and you'll feel genuinely welcome. See the California Rally Series website for everything you need to know.