Holley instructions contradicting on fuel bowl level ??

You got it.
.110" diameter
7 lb/sq in x 3.14 x .55 x.55 = 6.6 lbs force

.120" diameter
7 lbs/sq in x 3.14 x .6 X .6 =7.9 lbs force
Just saw this thread.
The force does increase by the square of the diameter - but you're off by a decimal place there (should be .055 and .060 squared). That brings the numbers down by a factor of 100, i.e. 0.066 and 0.079 lbs force. It'd take a pretty big float to push a needle closed against 6-8 pounds of force trying to open it! :)