I had to get on top of the AS today to remove the A/C cover to check for bugs. (See my gnat attack thread).
I did not find any bugs, but I did find something that bugged me.
The mounting screws for the plastic cover were put it so crossed that the heads were literaly cutting into the plastic making the hole bigger and oblong. Soon there would be no material left for the screw to hold.
This is a new Dometic Penguin A/C purchased and installed about three years ago. The rear two screws holding the cover on were put in so crossed it looked like they just put the screw in w/o pre-drilling and tried to find
the mounting hole in the metal frame. Very poor workmanship.
I always wondered why the replacement tops were so easily available. I bet these things go flying off at highway speeds all the time!
I was able to add some washers to keep the screw heads from cutting into the plastic and I got the screws straightened out.
May want to give yours a look before its too late!