I would sign up for it. You've got weeks and weeks to prepare. By prepare I simply mean:
1) Get your buoyancy under reasonable control. This means get yourself to the point where you're not popping to the surface all the time, not that you have to have the within-3-foot spec of a tech pass. Don't go crazy; if you occasionally float up 10 feet but catch yourself before popping to the surface, that's plenty good to take the class.
2) Look up the gear requirements (
GUE Fundamentals | Global Underwater Explorers) and make sure you're close enough to get the most out of Bob's ridiculous skill with fine-tuning your configuration. That basically means you want a backplate with one-piece harness (ideally with the d-rings in the approximately right places), a long hose, and JetFins. Yes, JetFins. They're like $30-50 on eBay, and they make a huge difference in your ability to trim yourself out, since they're so heavy. If you don't have a wrist-mounted computer already, go to your dive shop and have them wrist-mount your computer. A primary light is not necessary; backup lights actually help keep your d-rings down and so despite not being necessary, I think they're worth if if they're in your budget. You can usually find used Scouts with boltsnaps for $45-60, or you can buy the Piranha Penetrator IIs, which put out more light but aren't quite as well-configured (the rear hole is off-center). Don't worry too much about the little things like the inner tube bands on your harness; there will be plenty of tweaking in class no matter how close you think you've gotten your equipment. Don't switch to a drysuit right before class if you can manage the class at all without.
3) If you have time and can afford it, take Primer. I didn't, and it's not necessary, but will speed things along and help you get the most from your Fundies class.
4) Most importantly, chillax. Just go into it with the attitude that you're there to learn, and don't ruin the class by stressing out too much about the 'pass.'