Dang, flu, too bad I didn’t see this a couple days earlier; I would’ve recommended that same video. My spring busted a couple weeks ago and I went (superhero voice) TO THE INTERNET!!. Found that very video, ordered the springs and the winding bars online, and did it myself. $43 for the two springs and the winding bars. They bungled the shipping, and I had to wait a week and a half, but other than that it worked out good.
In any case, for anyone else considering the project, I second the recommendation of that video. The guy shows you everything you need to know to do it safely, and he has a nice demeanor. Also, the winding bars are quite inexpensive, and I would highly recommend buying a pair. Winding the springs, especially near the end when they’re really tight, is a tad unnerving, especially having heard the stories, and knowing I had the right tools made me more confident that I wasn’t going to screw it up. I didn’t wear a helmet, but only because I didn’t think of it. That’s a pretty good idea.