The Vac drop when the throttle opens is normal
and then it finds it's new equilibrium so to speak.
Your numbers are more like I would expect, and you should find out about the moisture on the carb... mop it with a kleenex and take it out side and put a match to it... If it poofs you know it isn't water!!!
You didn't really mention how the truck ran up the hill and that's really why I'm writing cause like others watching I want to know if it's any
better!
