Thanks all for all the feedback and insight.
The pods are completely independent of each other with their own controls, motor controller, etc., and can be run with differential thrust. A failure of any component in one drive won't impact the other, so I should have get-home capabilities. They will share three batteries that will typically run in parallel with each other but will be able to be isolated if needed.
As to low-speed maneuverability, I will have the differential thrust of the two pods and the front mounted Vetus bow thruster which I believe is rated at about 3000 watts. It's the smallest they make. Anything longer than a half second blip of the joystick sends the bow sideways in a hurry.
Currently, reverse rudder authority is basically zero, with a pronounced prop-walk of the stern to port. With the new pods I'll should no longer have any prop-walk and can use either differential thrust or the bow thruster to get the boat pointing where I want it.
I don't think rudder authority going forward will be an issue either. I've inserted a very rough image of the anticipated arrangement of the pods versus the existing prop indicated by the red lines. I will fair the aft end of the full keel to both seal up the shaft log (that will remain embedded in the keel) and smooth the water flow off the trailing edge of the keel. I'll mount the pods as tight as I can to the centerline, which should put their wash down each side of the existing rudder. Currently thinking about 4" of clearance between the prop tip and the keel, which is the same as the minimum distance from the top of the prop to the bottom of the hull.
As always, all ideas and advice are greatly appreciated.
Lars
For reference, the current prop in red is 17"x12", and the pod props are 12.5" x 8.3"
Actual picture of existing prop and rudder are the second image
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