1 - 3 hours
Well the wife forgot the Mac was nearby while watering a plant and that was all it took. She didn't turn it off and tried to shake the water out. I let it sit for a few day after getting the water out of it, but the keyboard was toast.
All went pretty much according to the guide. The display cable was tough to get off. Another issue was the purchased torx screwdriver started spinning in the handle about when I got to the display brackets. Had to improvise to get those screws out.
Take your time. Have a lot of light. It's doable.
Tri-point Y1 Screwdriver
TR6 Torx Security Screwdriver
MacBook Pro 15" Unibody Early 2011 through Mid 2012 Upper Case