Good suggestion CrossRoads, I was concerned about the voltage drop of the tip125. As well as the power dissipation problem, it would also have limted the choice of leds to those with a low forward voltage. I remember the op had some leds in mind with Vff over 3V, which would have been out.
So a pull-up (down?) resistor will be needed on the gate (10K?) and a low series resistor (100R?).
Another option for driving these fets would be to abandon the 9th shift register and use Arduino outputs directly, if 8 are available.
Paul