Bit of wiring help

[McFall1984]

I kept thinking maybe you got it wrong lol

If I'm down today ill wire it that way
Prob be tomorrow though as he rarely opens the shed on a Sunday

 

[McFall1984]

Ok we now have it wired correctly we think

We now get it to 0, but when we hit the key to start her it must recalibrate?
We have the red wires into the switched live, couldn't be a constant live as the gauge will always read

When running should the car read -.7 bar? Then when in boost it reads up in the +?