<VV> dancing vacuum readings questions

[Ramon Rodriguez III]

Hey guys, After getting the hesitation completely gone from Missy's 61 a
few days ago it came back a day or so later (though not nearly as bad).

Today I spent some time on the car and now it's running really well (for
the moment) but I was left with some questions.

The vacuum advance is once again not moving visibly when I goose the
throttle with the car in drive and the parking brake set.  To troubleshoot
this I hooked a vacuum gauge up to the vacuum advance line to take a
reading and see if I was getting enough vacuum that the advance should be
moving.  I was only getting five to seven, not enough to move the advance
which I think is supposed to start at around eleven or so?

The first question; is it normal for the vacuum gauge to be rapidly moving
back and forth, creating a "cone" covering a range instead of a steady
needle, or does this indicate bad valve adjustment or something?  When I
open the throttle while connected to the ported vacuum the needle on the
gauge creates a cone that covers from about five to about seven.  The
vacuum gauge I use is one I took from one of those aftermarket gauge
clusters people hang under the dash.

I also hooked up to the vertical vacuum line that goes to the choke
pulloff, on that line I get a similar effect but instead of the "cone"
covering a range of two it covers a range of about five.  I don't trust my
memory right now but I think at idle in gear the cone was covering about
twelve to seventeen.  If that doesn't sound right don't give it any real
thought until I go out and make sure that I'm remembering those numbers
correctly.

Thanks for any help,

Ray R.