foglight problem

I have a 1998 306 1.4 LX.
Strangely, I can't seem to find any information anywhere in the handbook on how to change the front fog bulbs, despite there being instructions for every other lamp on the car. There is no mention of what bulb is required either.

So...
Can anyone help me with
a) The proceedure to remove the lamp unit to get to the bulb, and refitting the lamp unit
b) What bulb I actually need, to save me having to remove the lamp unit twice

Any help much appreciated.
Matt.

there's normally two screws either side of the lamp cover undo them then remove the bulb and put the new one in and put it all back together