sim600,

With the standard MO5 kit using the plastic front knuckles you only use a short 5mm ball stud.

It is only when you fit the Alloy MO5 front knuckles that you have to use the tall 5mm ball stud. This is because the MO5 alloy knuckle is the same as the MO3R knuckle.

The plastic MO5 knuckle is of a completely new design and has the arm located towards the top of the knuckle.

Regards,

Calvin.