Create a new WingKIte from a big Kite

Hi, is there anybody out there who has refit a big Kite (Kitesurf kite e.g. 9m2) into a small Kite wing (e.g. 4m2). Seen one video where a guy just cut out the middle part of a big kite and used a sewing machine to sew the two outside parts together.
Eager to do something similar.
Maybe somebody who has done it as well?