[smuzz]

Yes - that would do the trick.
Try putting some temporary pieces of tape flat across the rudder and fin on one side just to hold both parts in the correct position, then you can put tape into the correct hinging position on the other side - remember to push the rudder into a full-deflection position and then tape right down into the hinge line. Turn it over and remove the temporary pieces and then push the rudder rull-throw the other way and repeat.