[dmsfrr]

It may(?) be possible to install a missing long tube from the passenger side if the valves & valve springs aren't in the way. I've never tried it, and it may be a one-way procedure???
If you can figure a way to see if the long thin tube will hold some lung powered air pressure when the other end is temporarily plugged, that would tell you if the tube is in place and in potentially good condition.
If the old tube is in there and damaged I'd guess the manifold needs to come off to replace it. OR, just plug both ends of the small hole where the tube is, but then you'd have no hot air for the choke. I don't know if an electric choke cover will work on a teapot carb. I've heard the coil spring may be wound the opposite direction???

Photo 3 above is the outlet tube on the passenger side. It may be a photo of a '57 but they're 99% the same.

Here's the only photo I have of the '56 driver's side, it's not very good.