We'll see if this lasts.
In case anyone is interested, here's how I mounted my E-field preamp and antenna, for the time being at least.
A junction box from the local Do It Yourself store, electrical (not plumbing) section. The box is just the right size, but the Fconnector takes a bit of careful attachment with a needle nose pliers (all the time remembering Mike's 'ham handed' approach).
E1. jpg here
Then I put a small notch in the supporting tube a few inches below, to provide a place to put a zip tie around the coax. In order to make a little more gripping area, I measured where the notch would be on the coax, and applied some tape to create the 'pig in a python' bump for the tie to grasp. I realize that the notching significantly weakens the pipe, and I might think about wrapping it with something substantial to restore the strength but it doesn't seem to bad, especially after I wrapped it with tape for the seal, then applied elephant snot over it to really keep the moisture out. Coax seal tape would probably also work, or the 3M self vulcanizing tape.
E3,4,5 here.
More in next response.