Solved: Duh, how open cartridge area??

My newish Canon Pixma 6320 black ink is out, have the new cartridge, can't seem to reach the area that houses the inks! Tried lifting every part, the scanner lid, central lid (can see the inks under a black plastic roof that won't open), and the paper trays.

I feel like a dope, but, if someone knows how to get into that area, so I can replace my cartridge, i'd be so grateful for your expertise.

Really, can't find a button, place to click or unhook, zip.

Thanks!