A few things you can do.Where the steering cable end is bolted on the arm of the turning nozzle,redrill the hole closer in to the nozzle.That will give you a little more turning.You can also buy an a/m turnplate (steering) which will have several holes or slot to move the cable end away from the center the turnplate. This gives more throw.
As far as a ride plate goes,buy an a/m ride plate,cut it off right where the end of the ski is (first),then if you still are not satisfied,then do a D cut.Should be several threads explaining this....
Several venders on here sell ride plates.You may even find a used one