Black Mesa - On/Off Lever
Creating an On/Off lever in 
Black Mesa is simple. Some of the steps are similar to the Pipe Valve tutorial, with only some minor things to change.
Introduction
First of all, we're going to create a func_door with the name door1
Later, we're gonna make the base. For that we create a prop_static with the world model 
faf_lever_box.mdl
Later, we create on a prop_dynamic with the world model faf_lever_handle.mdl, this will act as our lever/crank.
Until done, we add a func_door_rotating with the name "button" and the INVISIBLE texture, this will make the prop_dynamic move.
Warning:It should be prop_dynamic_override instead of prop_dynamic, remember that!
We create a new output, in this case, the OnOpen. Then add the name of the door (door1) and set as value Unlock
Note:Make sure you put the door as locked in the flags option, otherwise won't work
In the lever/crank (prop_dynamic), we're gonna add as a parent the func_door_rotating with the name "button"
