The procedure goes like that, remove power cord:
1. Remove the side end caps (3 screws each side, watch out (for re-assembly) as there is 1 short, 2 long screws)
2. Remove the Display bezel. Lift the right edge of the bezel slightly with your fingernail, then slide the entire bezel assembly to the right. It should easily pop out.
3.Remove the two screws on either side the bezel and set them aside.
4. Remove the 3 screws on each side of the control panel (i.e. located on the side of the keyboard where the end caps were,on the very top)
5. Lift the control panel: Lift the metal top FROM THE FRONT and lift off panel assembly with cables still attached. Tilt the panel back and prop it up using the slot in the top of the metal extrusion. This slot holds the control panel propped up like an automobile hood (Do this with most care, as there's the chance you could break/bend the plastic front-panel).
6. Now you have access to the SIMMS SLOTS from above.
7. Ground yourself by touching a grounded object.
8. Remove old Memory Simms (if necessary).
9. Install new Simms, refer to the EOS manual, especially if your not going to 128 MB.
While applying a slight downward pressure on the top of the SIMM to keep it from popping out of the socket, tilt the SIMM board into a vertical position. You should hear an audible click. Make sure both sides of the plastic tabs have latched.
10. Reassemble the unit. Lift the control panel out of the slot and slide the rear edge back into the horizontal slot in the rear extrusion (take care !)
11. Replace all the control/display panel/end cap screws. Done.
12. If all went right, it should display actual ram during booting procedure, or you can check via MASTER menu.
If there's a problem then most likely the SIMMS are not sitting right in their slot, do it again