MacBook Pro 15" 1260 - logic board defective and audio jack broken off in the left I/0 audio port.
Replaced both fans - left I/0 board and logic board using ifixit guides. Guides were superb, repair done in no time and machine working perfectly. I replaced a 2.5 board with a 2.6 and have a slightly faster machine too!
No too difficult - just be methodical and follow the instructions in the guides.