Found this optimistic (so I thought) build on youtube, showing almost the entire project from houseboat hull to completion!...and it works 
http://www.youtube.com/user/TheBoatman11/videos?view=0

Great to see.  There are lots of youtube clips; I have gone to only one, and haven't ascertained the waterway yet.  I haven't been to one showing the interior either.
It is a different vernacular from an Australian vessel, but is of comparable size and level of adventure.  I would never have doubted the feasibility of the project.
Every time I see a sternwheel photo now, I look for a Pitman arm: this one appears to have a chain drive.

Roderick B Smith
Rail News Victoria Editor