Thanks for the helpful replies.
I was aware both master and secondary must be calibrated but I hadn't realized the HUD function would be impaired if i didn't alter the set point on the secondary.
You just know I am going to forget to switch it at some point
I assume the pressure transducer hole is the little one on the face plate?
DOH

Set solenoid to manual... obvious. I should have figured that out for my self.
Still loads to figure out.
Thanks again.
ATB
Mark Chase