Anthony's instructions were fantastic--big kudos for helping out!
I would add that you should have a normal tape nearby so you can check out whether you've put the new one together correctly. The physical tape must go around all the little loops in an identical fashion! The other thing is that in my experience, releasing the spools by pressing the side button does not make it possible to rotate the reel, so don't freak out if you find that you can't move the reels around. Good luck!
Humble Pie, April 2005