Power Valve Issue?

[pusherfans]

Okay, I finally had a minute and got some info and have a novice stupid question.

I pulled the TP and threw it across the room (not really)

now I can see and work on the carb. I hooked up my brand new Holley vacuum gauge. Warmed up the beast.

measured

7-8 inches of hg at 1000 RPM (what consider normal idle for that thing)

Current power valve: 8.5

conclusion: pip rich due to power valve being open most of the time, specially when I am just kissing it where it was already rich with the stock power valve.

Novice question: I am assuming that the vacuum reading is related to the mechanical components of the engine (cam, intake, carb, air cleaner, etc) and not matter what the mixture, rich or lean, at 1000 RPM, at a given throttle position, it will always read the same vacuum, assuming all mechanical pieces are constant and the mixture being the only variable. (yes, changing the mixture will change the idle speed, but then I would I would correct it by changing the butterfly to keep 1000 RPM. Is this a correct assumption?

why I ask is because, I want to know if I can use this reading to get my 3.5 power valves or if I need to get the stock power valves back on it, adjust the idle again and re take the vaccum reading to see what power valve I need.

This is just step one in my plans. I have all of your previous suggestions noted for the next steps, should my last attempt t make it run right fail.