Mine is also a thermactor equiped california car. That is the tube I need just don't know where to find one. Somewhere in the past it was cut off at the vacuum block in the intake and a rubber line run all the way from there. Probably from getting damaged somehow. It really is harder to find parts for a 6 cylinder than a v8.
btw, my trans and thermactor had lines running to the vacuum block in the intake, not a split at the booster. Though that could have been changed somewhere along the line. There are two smaller lines that come out the side one immediately connected to a metal line that came around the back to the smog and the other a rubber line to a metal line at the top of the bell housing and a larger screw-in towards the front that went to the booster. the screw in was cut short.