I was bleeding the clutch fluid on my 2002 1.8 VVC SV recently and noticed that there is some free play in the clutch slave cylinder - as in, you can take hold of the front end of the slave cylinder and move it around, a few millimetres, up & down and side to side. Naturally, this play vanishes when you depress the clutch pedal, but explains the faint metallic 'clack' that can be heard when you de-clutch, as the cylinder moves to take up the tiny amount of slack between its rear face and the bellhousing.
How is the slave cylinder supposed to be fixed to the bellhousing? I can see that the rear end of it goes through a hole in the bellhousing flange, but is it supposed to be fixed in there somehow? (I imagine it is.)
If it makes any difference, the slave cylinder is a blue anodised item with an M6 bleed nipple fastened into an M10 (I think) brass fitting on the rear end of the top surface. Please don't ask me for a photo, as it's almost entirely concealed below the inlet manifold and behind some cable trunking, the coolant pipe, etc.