flush mount control removal??

[Yippee-Ky.eh]

can anyone give me a quick how to on flush mount control removal. I have removed the handle, plastic bezel and 3 screws on the aluminum piece behind the plastic bezel. The panel it is attached to is supposed to simply slide up, but I cannot remove the round aluminum piece behind the bezel. Are there attaching screws from behind? Thanks in advance Brian

 

[boscoe]

What control box type is it? By brand and model.

 

[Yippee-Ky.eh]

Sorry forgot to add that its a Yamaha 6xo-48206-12-00, after scraping off all the corrosion and removing the plastic insert I found 4 more screws--- as long as I can get the screws out I should be ok. Thanks for your reply, much appreciated