I'm also a newbie, but you have a type ss, right? That 12SS engine can rev pretty high . I heard one at my LHS. Anyway, about the full throttle thing(that sucks ), it wasn't good, but if she's still running, you should be okay. You can pick up a thermal monitor on towerhobbies for around $35(I think). One turn is one complete revolution (360 degrees). About the clutch, i'm not familar with the one that comes stock, as the only nitro car i've worked on is my own (nitro rs4 2) which I purchased used, and it came with the racing clutch ($15 on TH). There should be a way to adjust when it engages, as with mine you can set it 3 different ways (there are 3 holes on each side, so you just pick it up off the flywheel and stick the flywheel pins in different holes). That clutch would be a great upgrade since you have a 2speed.
You picked a great car, and I hope you enjoy it. BTW, please tell me how that engine is when you run it full throttle (it's hard to keep that finger half-way, isn't it ) because I'm thinking about getting a 12SS for my ride. Good luck, Josh