You mix up the c and x in the model number? I only see Dimension L (bla) cx on the support page 
From the dell support page:
To remove the bezel, perform the following steps:
Remove the computer cover.
While facing the front of the computer, press in the bezel release tab the top of the chassis.
Swing the bezel away from the chassis, disengage the two retaining hooks at the bottom of the bezel, and carefully pull it away from the chassis.
To replace the bezel, fit the two bezel retaining hooks into their corresponding slots on the chassis. Rotate the bezel toward the chassis until the bezel latches into position.