Same as Raskal. I don't remove the cover plate.
I have one of those collapsable tables that I unload my PA on to. Give it the full rinse down from above, then it goes up on its side for a rinse of the bottom.
While it's on its belly, I rinse down the wire hole, then when it's on its side, I hit it hit with the hose from below. Some sand and whatnot comes out but nothing major. Then when I roll it back onto its belly, another shot of water from above.
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