Motorcycle Repair: My 1981 Suzuki GS 450, suzuki gs 450, vacuum hose

Question
I have a 1981 Suzuki GS 450, and I have no idea where to plug the vacuum hose from the tank.  I've heard there is supposed to be a brass plug on the outside of the right carb, but the only two plugs on the carb are for air in the middle.  Now would it maybe be on the rubber seal to the engine?  Or maybe near that, cause I have seen pics of something to that affect.  Thank you
Clint

Answer
Clint,

-it should be on the right carb.
Look near the front or where the
carb goes into the rubber mount.
It should be near the inside top
of the carb, might be hard to see.
It will be a small tube sticking
straight up.

-There are some bikes that use a fitting
on the rubber engine tube or seal
as you called it, this is usually
for synching the carbs with vacuum gauges.
Hope the tube is still there?

http://www.cmsnl.com/img/Suzuki_CARBURETOR_MODEL_D_GS450_1982_SZ-partslist-big-S...