Thanks Gilly and Jim
Gilly, yup, got some pointers on taking the locking mechanism loose but wasn't clear that you could take the lock loose without opening the glove box door first. Haven't tried to take the box itself out yet... was too absorbed for the rest of the day reading the owners manual and other paperwork I found in the previously locked glove box. A regular time capsule! I'll take the box out this coming weekend. Appreciate the pointers and will look for cable coming loose from the box.
Interesting that power antenna isn't used for anything. My car does not have the cell phone option installed... if Mercedes put power antennas on their cars that aren't attached to anything, seems pretty silly. I may just disconnect the power lead to the antenna motor. One less thing running all the time.
Again, thanks for all the help.