XRAY - Model racing cars

I've recently purchased a T3 and the Hudy Ultimate Setup station and have been working on some setups for the local track. I find the station easy to use except for the tweak.

I attach everything to the car as the book says and place on the tweak station, press down on the front and rear shock towers to settle the suspension and take a look. What happens then is I notice if I tap the tweak station at the edge where the measurement ticks are, it will not settle back in to the same location each time. This makes me think that trying to adjust for this is useless since I can't be sure I'm getting an accurate reading.

Is there a trick to getting the car to settle properly on the tweak station so that I can make adjustments and recheck with accuracy?

Thanks!

My view would be that if you press the front and rear shock towers in the same place each time you will get consistent readings. I put a finger on each of the two extremities to depress the tower.

When I use a tweak station I always push down in the centre of the car on the top deck so it's trying to compress the front and rear the same amount at the same time, as you release you should find the same readings again and again.