<VV> powerglide car hesitates off the line

[Ramon Rodriguez III]

Hey guys thanks for all the help.  Advancing the timing to where it should
be seems to have pretty much solved the problem.  It's like a whole
different car now =)  I'm still having a little intermittent trouble with
the idle, occasionally when I stop the car the idle is really rough and low
and sometimes stalls.  If I can goose the pedal a little without stalling
it it clears it, if I stall it and restart it it is also gone.  I'm
thinking maybe a little dirt in the fuel?  I'm going to try Bryan's
suggestion and see if that solves it.  I did check the plugs by the way and
I did replace them with new in the fall when we brought the car home.

The vacuum advance is now working as intended after setting the timing
properly.

I have another issue I'm a little worried about.  When driving the car I
hear something I can only describe as a clicking coming from the rear of
the car at low speeds with the window down.  Clicking isn't exactly right,
it actually sounds a lot a noise a bicycle might make.  This sound is
rhythmic and changes speed with the car.  I jacked up one rear wheel at a
time and spun them and found that the noise was coming from the
differential end of the axles rather than the wheel ends.  I also found
that I'm getting the same soft click from the diff on both sides so it is
likely it's the diff making the noise and not the universals.  I checked
the gear oil in the diff and it is at the proper level.  Interestingly I
think this sound is not present when the car is driven for the first time
of the day but appears after just a couple minutes of driving.

Thanks again everyone,

Ray