Hello Al,
I will try to explain the attached file and the workflow. First you have to create your surfaces. I have used here sweep with a circle placed to the startframe (getCrvSFrame). Important: Switch of CapEnds in the sweeps!. The created sweeps are connected to the nodes BRepNameSubObj. This node takes the sweep and gives edges and faces a name. If the elephant runs, it creates also a tempobject with the same names. Now you can preselect both edges. Do not clone the BRepNameSubObj node, because the clone would have the same basename for the subelements. When you now create the blend the names of the edges will be evaluated and stored in the blend node. Connect the wires and switch of the tempobjects in the BRepNameSubObj nodes.
It's a little bit complicated, but at the moment I can't find a better solution for the function.

Have a nice day
Karsten