2005 Speedometer dissassembly info

My speedometer vibrates up/down way more than the tachometer. I have to open the gap between my clock pod. I want to be able to tighten up the mounting hardware but I'm unsure how to get the reset knob off. Since the bike is very old I really don't want to over-stress the knob getting it off. Suggestions?

If I remember right look inthe end of the knob and remove the screw.