I found the cheapest, simplest and good working solution for lighting my blue trackball.
A simple plug-in night light bought at one of those "Everything $1" stores.
I mounted it under the trackball to the base of the cab with a velcro strip. It is plugged into a 4' household lightduty extension cord and that runs to my power strip. So the light comes on along with the rest of the cab when the main power is switched.
Just thought I'd offer a super cheap solution since we all know how much $$ our cabs can end of costing.
Rick
Hey 1up