Heater Core Front Cover Plate

[Mark in KS]

I'm spending Saturday on the Benz to replace a broken heater control line.  While I'm under the dash, I might as well go through it to make sure everything is perfect.  Pulled out the blower and reworked the controls and flaps.....everything!  For some reason the front cover plate on the heater core is loose and free.  Is it necessary?  How is it fastened to the heatercore?  It looks like it was tacked to the core sides.  Any suggestions are welcomed.

[Mark in KS]

Whoops, nevermind.  The technical manual had a VERY good illustrative section concerning heater cores, control valves, etc.  I guess I need to re-weld it to the core.  Looks like a trip to the radiator shop next week is on the schedule.  On another topic, the foam gasket material and a new control valve o-ring are going to be pick up items from the local MBZ supplier, too.