This was the best I could find... I think it's mentioning to remove the DVD drive because you may be able to push up on the keyboard from underneath where the DVD slot is.
From looking at pictures of replacement keyboards, there is a single screw that attaches to the bottom of the keyboard (roughly top center):
http/www.super-laptop-accessories.com/songjunjie/ToshibaC850KB.jpg It *may* be the same screw that secures the DVD Drive.
http/forums.computers.toshiba-europe.com/forums/thread.jspa?threadID=68701
Before removing the keyboard, you would need to remove the ODD bay module (CD/DVD drive)
From my knowledge the keyboard is secured by 14 latches (6 at the bottom and front and 1 at the left and right)
TO remove the keyboard insert your finger in top cover left hold and push keyboard corner, so let keyboard corner pops up.
Then you need to release the 14 latches on the keyboard cover.
Start with six bottom latches, (the leftmost latch first, by the sequence to the right most.)
Then one latch on right side and one latch on left sides and the six front latches.
Then disconnect the keyboard cable from the connector on the system board and remove the keyboard.