Forget a Kort nozzle,a simple prop and rudder arrangement will be suffice,
The kort nozzle will not give you the turning circle you require,but with the standard
arrangement you will get the turning and propulsion you require.
Ask my missus,she rescued me and other boats on more than 1 occation,and she only knows full speed ahead.
After reading Brians post,do not use a t4a motor i have got some,superb motors,but not for a springer,built for power,
not speed,i recommend a 540 or equivalent