Overdrive button issue

The knob on the end of my gear shifter spins loosely, and now the overdrive is starting to turn on/off as the knob is touched, moved, etc. Annoying on the freeway.

Any ideas how to get this thing apart and fix it? Could be a loose wire in the switch, but I can't see how to get it off besides a good, hard pull. I REALLY don't want to try that without researching first.

1996 2.4L 4cylinder automatic transmission

 

Theres probably a ferrel the wire goes thru & maybe a "C" clip or set screw holding the knob assembly together, not sure but yeah def. don't yank on it

 

I didn't notice any C clip or set screw, but I couldn't get my fat head behind the shifter. I'll grab a mirror and take a closer look.