Mark -

It seems to me that doing even 20 miles a day is a long way to float on most any river if you want to do a reasonalbe amount of fishing and enjoy the float, intead of spending most of your time on the oars.

I have a medium sized cataraft and a drift boat and anything over 10-12 miles is a pretty long day float for me.

You didn't mention the size of your boats, but if you feel reasonalby proficient at the oars (and you have decent quality boats) you could consider a multiday float on the Yellowstone or perhaps the Madison in Montana. You could also arrange with a shuttle service, for example, to get around places (like Yankee Jim Canyon on the Yellowstone) that you wouldn't want to float through, or to get you or your gear to a camping area if needed for the night. The Missouri River below Holter Dam would be another place to consider, and would be easier rowing.

John