For the Vdd mod, connect a 20k VR between the red pin and ground. Decrease resistance to increase voltage. The green pin in the above picture will read approx 0.2v (or more) lower than the output voltage of the regulator. I would recommend finding a capacitor which is connected to the green pin to use as a Vdd read point.

I'm 90% sure that the voltage being increased is Vdd, but there is a small possibility that it could increase a differnet voltage, so increase voltage slowly at first.

I'll take a look at the Vgpu mod later.