How do you open the case on an Apple II GS?

[63dot]

I can't seem to find any place the Apple II GS opens up. The computer did have its case opened once by the computer user to install something and they can't remember how they did it.

Does anybody recall how that case was opened?

Thanks in advance.

 

[kgagne]

There are two plastic tabs on either side of the back of the case. Just press them in and tilt the case up from the rear.