That seems a little short. I run from the spinnaker bridal tang, and see where it touches the rudder (placed in the upright position). Usually touches about 1/3 of the way down the rudder. I must have a lot more mast rake.

What's your team weight? I was usually between 325 and 365. Used about 1 3/4" of spreader rake and 700 lbs diamond tension.