How do you remove the main board from an Onkyo receiver (A-RV401)

[onedumbquestion]

I'm forced to work on this board attached to all sorts of stuff it's so frustrating I wanna disconnect the board and put the everything else to the side while I repair the board Has anyone done this There are pins with bare wire wrapped spiral and other white connectors with grey ribbon power cables that I don't know how to disconnect either

[kingswoods]

The grey ribbon wires come off by pushing down on the top of the white connector and this releases the wires.