HP's video take apart instructions say nothing about how to remove the keyboard. It just shows it already out. I snapped off one esc key tring to pull it up and stopped there. HP was no help. I've removed a ton of keyboards from Macs and there are sliders at the top of them, and I assumed, most laptops. On the HP I slid the 4 locking sliders back but couldn't lift or pry the keyboard off. So, what's the secret?