Every few years my dad gets a new Macbook Pro from his work. When this happens, he kindly hands down his old one to me. Just weeks after getting my new (to me) MBP, I came back into my living room from using the restroom to find that my daughter had spilled milk all over my laptop. I was devastated. I immediately turned it off and put it upside down on a towel to let the milk drain out. I left it for a couple days, and it eventually turned on. Only that the keyboard wouldn't work, and it would boot loop every few minutes. This told me that the keyboard was gone (obviously), and that something was wrong with the power button (it was acting like someone was holding it down). This was before I knew the two were connected.
I used the guide on this website to take my MBP apart, and then just took the keyboard out completely. I was able to turn it on with a paperclip by shorting pin 5 on the keyboard connector and a ground plate. But this wasn't a permanent solution. Impressed with my work, my dad offered to buy me a new Upper Case. I couldn't use my old one since I had stripped a bunch of rusted screws detaching the keyboard, and the track-pad started acting weird.
Considering this was my first time taking apart a MBP, the repair went pretty flawlessly. The only hurdles I had to overcome were 2 stripped screws and the fact that I accidentally ripped off one of the connectors to the fans from the logic board . One screw holding the plastic casing to the right speaker in. And the other holding in the Mag Safe power connection. After trying every tool I had (including super gluing my screwdriver to the screws), I used my pocket knife to widdle around the plastic to free the speaker, and then just used a Mag Safe connector from an old macbook that my father-in-law had laying around.
And the fan connector... my heart sank into my stomach when it broke off. I knew that I couldn't sodder it back on since the connections are so darn small, so I used the next best thing. Super Glue. And it worked flawlessly.
I certainly wouldn't recommend my methods, but they certainly beat having to buy a $900 logic board just for a fan connector.
Don't be scared to get in there and start taking stuff apart. Read as much as you can about what you're doing before you do anything, take your time, and be prepared to exercise some serious patience. But the whole process really wasn't too difficult.
I'm not going to share any pictures because: 1.) I didn't take any, and 2.) they would look just like a brand new 2008 MBP