http://www.youtube.com/watch?v=Rmjp79A4y6A

Check out this link to see how the head can be changed using this technique if needed. If you put a wedge (GM makes one or you can make one yourself) down between the timing chain to keep the tensioner under pressure when you release the cam gears then you will not need to be concerned about the tensioner.

Owner caption August 2015 · Photo 4 of 5