I wont to buy a stroker kit and the man siad all you need to do is CUT and SHUT it??? What does that mean... 3

He means after stoking the engine you can simply put the same head back on it. Cut it- extend the throw of the crank or what ever work you plan on doing. Shut it- put the lid back on. The lid in this case is the head with the valves and such already in place because you are reusing the same head.