I would agree that it's surprisingly easy. There are lots of resources available online for wiring charts, the one i used was Seymour Duncan's site, which has a whole bunch of them in nearly every conceivable arrangement. There are also many different places to order parts from like stewart mcdonald, guitarfetish USAGC and warmoth for starters. The issue that sticks out in my mind of being the most problematic is ensuring compatibility - what kind of pickups is your guitar routed for, what kind of volume and tone potentiometers do the pickups require (250k? 500k? it will say on the wiring chart), does the pickguard have the same number of screwholes as the old one (mine didn't, but it just meant i had to drill a few holes. Scary! count before you buy so you can order more screws if you need to. hell, just order a bunch anyways), does it even fit - that kind of thing. If you're thinking of different strat pickups, you're in luck because there are a billion different kinds and they'll all fit that standard pickguard shape unless otherwise noted.
As for soldering, I used 60/40 rosin core electrical solder, and from what I read, it is absolutely imperative that it be rosin core. They also make lead-free rosin-core solder, which is apparently slightly trickier but hey, there ain't lead in it. If joining two wires, wrap them together so they have a solid mechanical bond in addition to the solder bond. there are a bunch of youtube videos that explain and show this way better. It may seem like overkill, but wear safety glasses. solder's hot. Work in a well - ventilated area. That's all i can think of at the moment. Finishing is a whole 'nother kettle of fish which i am kind of terrified about a little.
