Pinion angle movement with Caltracs...

I am sure there is a thread about this, but have not found it. I am wanting to get my pinion angle adjusted as I am sure it is not correct. In your experiences, how much movement of the pinion in terms of angle have you seen with your Caltracs with a car that will be in the high tens. I want to be able to get the centerline of the engine and the pinion pretty parallel under hard accel. I realize that the answers may be all over the board, but just need a starting point.

Thanks.......!