This is more for the video arcade guys I suppose but can apply to Pin2000. Is there a difference between a regular screw driver with an insulated shaft and what I have heard called a High Voltage screw driver?

Was thinking off adjusting the brightness pot on the tube but have been told to use a HV driver. Or is it just a matter of being extra careful and you'll be fine?

Just use a plastic trim pot adjuster.  They are meant for monitor adjustment.  Monitor boards are fairly safe.  Just stay away from the suction cup on the monitor itself and the flyback transformer.