[Kevin Sevcik]

sanddrag's shaft mounting should work brilliantly. I should've thought of that. at any rate, the mounting collar doesn't particularly support any side-loads. All of the load will still be supported by the shaft. With the flexible coupling, the shaft out of the drill won't support anything at all. You'll need to support the shaft in your wheel with a pair of bearing pillow blocks on the other side of the flexible coupling.