Chinese USB 3020 Limit Switches

Have been searching the vaults on the forum but drawn a bit of a blank. I recently purchased a China 3020 CNC router and want to fit limit switches to it, the board is a JP-382C . My hunch is is the white socket arrowed in the picture is where I need to connect the positive feed wires to the axis switches. So is there anyone here who can advise me further please?

Any help appreciated.

I didn't find the right solution from the Internet.

reference:
www.cnczone.com/forums/general-cnc-machine-related-electronics/347030-cnc-forum.html
Demo Video Cost

Thanks!