Unless you have a very sophisticated step assembly, you will not be able to move the step with the rig in place. The leading edge of the mast step should be located 1" behind the vertical face of the molded fiberglass step in the floor of the head (class rules max forward position). The headstay will be very loose until the rig is tightened per the tuning guide(s). Your sailmaker should be able to provide specific info on optimization. For example, North mains like much more prebend in the rig than Quantum or Ullman.
