My EQ6 sits out in the back yard permanently (except when I take it to Camp).
I cover it in a sheet folded in half, then a big sheet of thick plastic. Then I tie it around with some strong electrical cable as rope.
No, mine hasn't rusted. It has been living outdoors, inside a small leaking obs for a short while, and out on its own like it is now for about 4 years.
I do spray it all over with Surface spray though atleast once a month to keep bugs out.
I just carry out my scope and plop it on. Already Polar Aligned
It never misses a beat.
They get drenched out in the dew at night anyway when you are using them. All is good.