None at the top end, there's just a bearing that is in the actual "tube" the column sits in, you can see it under the indicator self canceller under the steering wheel, there are usually 2 bolts holding the top support to the metal work inside the car, these have a much bigger hole in them than the stud that passes through them, see they are nice and tight.
The actual bush has a outer rubber part that goes in the hole in the bulkhead, then the plastic part that sits around the shaft sits in this, this plastic part/s are normally 2 pieces 1 inner 1 outer, it will all become clear when you take the old one apart.
tabetha