Well, on the 3oz hayes, I do a couple of things.

I do use the tubing the tank comes with. I streach it a bit as I'm putting the tank together, that seems to help the flexibilty a little.

The other thing I do is this. When I put the clunk line on to the stopper, I give it a little tug to the side, so that while it's on the stopper fully, it has a tendancy to sit not-quite-square to the stopper. Now aim that part down, and you're good.

Oh, and don't sweat that this means that the clunk won't quite read the top of the tank in level inverted flight. Chances are you aren't going to do much of that anyway when low on fuel, and any negative G pushing will make the clunk reach. For that matter, you can probably just not sweat it at all, and chance are, you'll be fine.