Hoverboats in the new Snow Sims

I was mucking about with my Day Dreamer Flying Ship and noticed that how I had the hover part of the script set up doesn't work so hot. Evidently the hover height vehicle parameter has a top end and most of the land in the new snow sims is higher than that top end.

Is there some other way to get a vehicle to ascend and descend? I was thinking maybe loosening the z axis friction long enough to 'push' the craft along the z axis and then tighten up the friction afterward to keep it from falling, but so far, that hasn't yeilded a lot results.

hints appreciated.

Hover, as such*, is absolutely capped at 100 meters.**

* That said, nothing is mandating you use hover. I won't touch it with a 10 foot pole. Just thrust up and down the same way you do forward and back.

** Against whatever you set it to hover against. I'm assuming your doing global hover. Do ground hover and you can get up to 100 meters above the ground your hovering over... Which in the mountains can be quite high indeed. But this makes for a bumpy ride...

I've tried thrusting linearly along the Z axis, no dice. I must be missing something becuase that was the first idea I had...maybe its in the motor time scale or the friction.