First of all it is located roughly in the middle at the rear of the engine there are 2 wires on it which are on a black plastic support bracket.  It is tricky to get out only because of limited space.
Any problems with what it looks like have a look at one on ebay
1. remove the air filtter to gain access and remove  the 2 top bolts (13mm) at the top of the gear box 
2. jack and support the vehicle
3. underneath the car disconect wiring from the starter terminals (8mm and 10mm i seem to recall) 
4. remove the remaining starter mounting bolt (13mm) and manouver out.
refit in reverse order
                
 Andy L
                
 September 2005