Squeaking Sound Coming from 225 /6

All I can say, with all possible respect, you screwed up the install, left out a ferrel, reused a ferrel, kinked the line,
Plastic lasts nearly forever,,, odds are it was operator error. Not being critical,
Not my car & not my installation. But I learned from this, and I can see no good reason to install a mechanical o.p. gauge inside the car.