Hi Michael,
I tried to duplicate what you did, but when I select the two tube surfaces and then show points I get a set of points that describe rectangles. If I delete those points, then the tubes just go away. What am I doing wrong?

I wanted to extend the tubes above that flat surface but NOT below the more complex ends on the other end of the tubes (if that makes any sense). I can't find the original generators for the tubes, and, in any event, generating the surface on the bottom end of the tubes was quite difficult. I did it sometime ago and I'm not sure I can remember how to do it again. Is there a way to extend the tubes in just one direction, ie above and away from that flat surface?

What I'm going to do is open the drawing in Rhino and then use its unwrap command to produce a flat representation of the tubes. (See attachment to see what I mean.) I've done it before but I need to extend that tube in the one direction so I can add some other details to the flat representation. (I hope this is making sense.) Does this help you to understand what I'm trying to do?

Thanks again,
Mark