Before starting this process it's important to note that the eMac can have some seriously dangerous voltages inside of it, thanks to the CRT display. Before working on an eMac, you should unplug it, press the power button to clear any stored charge on the motherboard, and then let it sit for 24-hours (or more) to allow the CRT to discharge.

You can read more about CRT safety procedures here. If you aren't experienced with working on devices featuring a CRT, it's recommended that you don't proceed any further.

On the bottom side of the eMac, remove the following screws:

A single 2.5mm hex screw

Two #2 phillips screws