HDD magnets are a great idea -- strongest magnets I have laying around too...
With your design, have you looked at the airflow for the condenser? I believe the front of the unit (on the outside) is the outgoing hot-air flow from the condensing coil. If you a fresh-air inlet, I think the fins on the side pull that in (optional and not the most efficient setting).
Have you checked for the warm air flow by the front panel? Otherwise, the shade would help. I think one of the links earlier showed a spray with red dye for for unit's stand-alone unit's exhaust fan (the amount of air flow is considerable -- it nearly reached the top of the test home.
I thought about some sort of shading as well, but I'm afraid of choking the flow. It would have to be a tall, awkward looking fence -- but that unit sure bakes (near the Southwest corner with no shade protection). Hopefully the mist is doing something other than scaling the living daylights out of it!
RH77