You really, really need to consult a reputable PP trainer... not every dog has the nerves for this (I'm not sure what you mean by high pain threshold, and that's not always an indicator of stability), nor does every owner. I have to put a really heavy emphasis on REPUTABLE, as there are a lot of fools out there advertising training "attack dogs". They're the only ones that can evaluate your pup for the right temperament.
Is your interest in sport (i.e. IPO) or true protection? If it's true protection work, just having a well trained GSD is usually enough of a deterrent for the average family. If you're feel there's even more of a threat, having a dog won't deter someone that crazy, no matter how trained the dog is. PP training/maintenance is definitely NOT a hobby.
If your interest is in sport (which is the impression I'm getting), then find a local training club and get in touch with them about coming out to visit and watch-- it's a lot of fun and a great hobby.
In the mean time, take obedience classes. A high drive puppy is going to need the outlet, and if you're inexperienced with the breed (not saying you are, just if) then learning how to manage this drive in someone experienced with working breeds will really enhance your experience with your pup.
Good luck, she sounds like a blast!