Dave, Tiber is holding ducks as we speak, lots of ducks. There seems to be a lack of geese though, but that may change at any moment. There are lots of good launches around the lake and good camping spots at Stafford Park below the dam and the VFW Campground above the dam, it also has a launch site. Your boat may be a little small if the wind comes up but there are plenty of places to hole up, it just might not be fun.
If I were using a prop boat on the Missouri, I would stay below Ft Benton, probably around Loma, there is a good launch and camp ground on the river. The Loma Cafe is owned by a fellow duck hunter and the food is out of this world and not yuppie expensive.
Like with all waterfowl hunting timing is everything. As I said about Tiber, we put 5-8K Mallards to bed in the stubble last night after shooting 4 limits, and they had to return to the water so finding them is your only problem. Birds had been trading all day is the way we found their feeding area, and another two hours getting permission. There is lots of BMA-State Trust land that you can access all around the lake, and much of it is ag land, and I believe all the boardering shoreline and islands are BLM so no problem there.
In the past my crew has had some good shoots on Tiber, we use a Lund Tyee to get around and sometimes it can be rough.
I hope this has been of some help, you will notice I didn't give you GPS coordinates, but the ducks move all the time.
Enjoy if you go.