Grip pressure and pressure points

[Monkeyboy]

What is the consensus regarding grip pressure at the pressure points when hitting?

I'm new to TGM and I've been focusing on the pressure points while practicing. I am finding that my hands/forearma are more tired than in the past (before learning about the pressure points).

So either the movement is just new to me and new muscles/actions are being employed - or I am gripping too firmly at various points.

My first question is what is 'normal' grip pressure at the 3 pressure points? (Lets say each pressure point has a 1(lightest)-5(firmest) scale.

My second question on pressure point 1...is the pressure applied more by the thumb on the shaft, by the palm pressing into the thumb on the shaft, or both equally

thanks
~Monkeyboy