The plastic tab does stick up & make contact at the appropriate time with the tab that protrudes from the lower portion of the LCD housing.
What I'm assuming is that the tab I have to "flick" in order to get the LCD to light up is actually a lever that makes contact with a switch deeper inside the laptop. Its the alignment of this tab & the assumed switch deeper inside that laptop that I want to adjust.
If I push on the tab that sticks up from the laptop, simulating the LCD being closed the LCD lights turns off. When however I stop pushing on the tab, more often than not the LCD does not light back up (even though the tab does return to an upright position). It remains dark until I flick the tab. Even then the light will often flicker momentarily only to remain off until I flick the tab "just right".
I appreciate your patience while I attempt to describe this problem.