If this is being performed from User Diagnotics, the instructions on the dc0604 screen will lead you through the procedure.
10.00 is a pretty large jump, this is the full width of the reference graph.
Ensure the skew you are seeing is not being generated by a particular paper tray or stock.
A skew this large that is not correctable may need your local Xerox Service Team to be involved.
hope this helps
Technical Escalation Support - Technical Solution Center