Well I've been playing with it, and I'll have to keep playing with it
After converting to polys, extruding faces is, so far, making a mess. I'm guessing I need to finesse the tessellate options when converting to make something that will extrude cleanly. It just seems that I should be able to build the thickness into the birail profile, but I haven't ever had any luck creating such a surface with closed paths to create that thickness. The tool only seems to like open paths with point to point connections to the rail curves.
I'll keep trying, but now I have to get back to work
Thanks again everyone!