can the filter/flowplate assembly be separated for cleaning?

I've taken all the insides apart and cleaning them all. I think I have fixed my drain problem but before I put it all back together, I want to clean the flowplate assembly but I can't get all the gunk/sedement out that is trapped behind the filter/screen. Can this part be disassembled or is there another way to clean the inside?

I have tried baking soda/vinegar, hot water, dish soap cleaning....

Thanks!