Light switch knob removal?

[Bullett]

I need to remove my new light switch that I installed a couple weeks back because I will be replacing the wiring harness. For some reason, I can't seem to get the knob to separate from the switch. I remember you need to pull the knob all the way out, to the "lights on" position and then push a release button. This switch that I installed, which I believe is an aftermarket switch even though it looked exactly like the original, doesn't seem to have any release button. There is a spring loaded type button on the side opposite the side where everything plugs in. Is that the release button?