A/C compressor rattle

[Darren Calbero]

I found the source of a metallic rattle that occurs while my engine is
running.  Between the A/C pulley and the housing, there seems to be a cover
plate of some sort that is loose and is being knocked around.  I have yet to
take the belts and the pulley off to fully survey the problem but does anyone
know if this may just be a case of a few missing screws to hold said plate
down?

In the event that there is more to it than a simple screw
replacement/tightening, does anyone know the correct belt size for the
alternator (no A/C) with a UR crank pulley?

TIA,
DC