I recently bought myself a Squire Fat Strat, the original pickups sound good. But I want to replace the Humbucker with a Seymour Duncun. I have been playing for along time. But I have never changed out anything (hardware) on my other guitars. I just feel that this little Fat Strat would be oh so much better with the S/D Humbuckers. Thanks for any info.
Fenders Rule!
two tips

1. ALWAYS sketch out original wiring configuration, it will help you but the things back together if you mess up
2. If you have never used soldering iron - DONT DO IT NOW, get someone more expirienced to do it
3. try to cut as little wire as possible from the pickup itself
I started a new wave in music - it's called n00bism...
Oh wait, Curt did it before me
Kramer pacer
Screamin' deamon (neck)
Live-wire metal (bridge, 18v)
Finaly knobs that go to 11
No reason to cut any wires. Hold the tip of the iron to where the wires are soldered to the pots until the solder releases. Wire the new pickups in the same way the old ones were. Hold the tip of the iron to the connection just long enough that it draw a little solder into it.
One of the biggest problems when soldering, is if you leave the soldering iron on the back of a pot too long, it will fry the insides, then you will have to replace one of those as well. Just leave it on there until the solder melts, not any longer. I have wired a few guitars, and as long as you're careful, you'll do fine. Check out this website for some great and easy to read schematics~

hope that helps ya out!