Yamaha MD4 Disc Lock Manual Bypass

My Yamaha MD4, recently sold, occasionally locks the disc for no reason, making it impossible to eject and switch discs. I called Tech Support about it, and they said I could either try this or send it in to be serviced. Of course I did it myself (that's what I do), and saved myself the hundreds of dollars that I would have spent fixing it. Here's how to bypass the disc lock function and eject the disc manually:

Please note, this is not to be attempted while the unit is powered on or plugged into a power source, as electric shock may occur.  And besides, what idiot would do that anyway?