My girlfriend had spilled nail polish remover on the keyboard rendering the uppercase and keyboard not exactly usable. I told her I could fix it. As soon as I got the money I ordered the parts. I was able to keep the laptop since she had gotten a new one.
I've been in plenty of MacBooks and I know the struggle you have to go through. It took me over 2 hours only because I took breaks and sorted the screws and read the steps for the replacement and to put it back together.
I had only ran into one problem which happened to be a stripped screw on the charger. I took the Torx screwdriver and was able to loosen the screw. I recommend using the T6 Torx for those types of things.
Take your time and be patient and take breaks. I am an impatient person but I know these things aren't easy. Keep organized with the screws and be tender with the spudger and cables. It is not as hard as it seems, just a bit time consuming.
Phillips #0 Screwdriver
Tri-point Y1 Screwdriver
TR6 Torx Security Screwdriver
MacBook Unibody (A1278) Upper Case (Non-Backlit)