Yup, what Gary said, your arm is upside down!! How do I know this?? Been there done that, bought the tee shirt...
Wait, you say the shifter mounts directly to the knurled shaft? In that case the shaft has to be mounted upside down. I sort of remember seeing this on the site before, and for some reason I think Marcarl knows about this...
In other words what Mel says. Didn't read his post until after I wrote this!