although light the draft is about 10", I figure 12 to 13", but run over a sand bar which is only 18" regularly. This is a very shoal draft for a 26 to 27 foot boat, even outboard powered. I had a 27 foot express cruiser, with a moderate V and I/O, and I figured that I needed 30" to safely run.
You can use a small kicker motor to run with the outboards all of the way out of the water, and the kicker running in the tunnel. See my album for a bracket I made to fit on the Armstrong bracket to take our 3.5 HP dinghy motor, which will push the Tom Cat at 3 knots in calm water.