[6pack] Moss SU Upgrade for TR6

[Alex]

Hello all,
A friend of mine just bought a 1970 TR6 that has the Moss SU upgrade. There
are two brass tubes (one ea carb) coming what appears to be out of the fuel
bowls. They are open to the air with nothing attached.

I was told they are over flow tubes and nothing needs to be attached. If you
put your fingers over the opening of each tube, the car will stall out. It
appears that they have a unction. If this is the case, I can only assume that
at the very least there should be some kind of filter mechanism.

Is anyone familiar with the Moss SU upgrade and what these tubes are for and
how they should be set up?

Side note - the car idles at about 1100, has a Pertonix coil and electronic
ignition.

Thanks,
Alex Manzo
72 TR6
59 TR3A