PACKARD BELL MH4000 - Manual (Page 92)

5-8
Upgrades and Options
5. Avoid bending the EMI fingers as you slide the
cover back very slightly (to about a 1/2-inch or less.)
Then pick the cover straight up from the chassis.
Figure 5-2. System Top Cover
A
Removing top cover
A Retaining screws (two at back)
To avoid damaging EMI fingers,
do not slide the cover back much
more than the 1/2-inch implied
here.