The guys over on Mike Anderson's forum http://www.trophyfishingtn.com/smf/index.php
like to use the Arkansas style fiberglass jons and Gheenoe style boats on the caney. I've never fished the caney but I'm assuming that it is a slow meandering type of river since these boats are popular. They would not be very good for rivers like the Hiwassee or Pigeon river coming out of the mtns. You would want something like a drifter or raft for those. I would think a flat bottom Jon would be good also. Make sure you get at least a 42 or 48" or wider bottom width jon, the 36" boats are tippy. You'll see a lot of 1436 jons for sale, they are too narrower to stand up and cast without feeling like your going to fall out. Keep an eye on craigslist, there a lot boats for sale right now. Many people out of work and selling or they are upgrading to something bigger or newer. I personally like the v-hulls over the low sided jons. I feel safer in them out on the lakes and rivers.
Talk with Grumpy and David Perry as they spend a lot of time on the middle tn rivers and can give you more insight to those rivers and the type of boat needed.
Joel is right, check out Tinboats for mod and restoration advice.