I initially had just a small gap between the rear face of the front pulley and a straight edge with it up against both pulley faces.  I made a minor adjustment (didn't take much) and things seem about as perfect as possible now.

If you're talking about the Chunk sound, do that again but make the belt pull something. Where it's engaging the drive pulley is so sloppy it looks like the trailing edge of the teeth are sometimes landing on top of the leading edge of the pulley. Can you get something to hang on the brake pedal to hold the belt back?
Watch it and see what you think.

Great advice guys. I gave it some rear brake with it spinning and things look better, but it was still raised up. I took it for a ride with the pulley cover off and I think it's OK. It sure didn't take much adjustment to effect a change, though.

Boy, having that pulley cover off exposes you to some new noises! I've been running with the belt covers off and prior to that was only running the large upper belt cover (plus the pulley cover, of course). This time I put everything back on and I'm not hearing the noise. Just a faint whine which I'm thinking is normal?

Thanks everyone for the tips and suggestions!