Well surprise, surprise...the first iteration didnt' work. Here's the second.

Ok, some time later, the second iteration didn't work either, but I was able to get some careful measurements from it to modify the design. The result: third try is the charm. Actually, not quite...the bending is good, but this particular section of tube was sort of squashed on one end, so the ferrule won't go on. Oh, well...at least I know how to make another one that fits. Notice the little string level shows the line is level going into the outboard bracket. Sweet. Here are drawings to make up the left and right outboard tubing sections.

...and from the outside, the line goes right through the hole for the tank support bracket. Perfect. I think I'll get some more grommets for these holes. Oh yeah...guess what I ordered more of last night? Yup...more tubing. Sigh.