Mk1 Focus Creaking When Braking

I've got a rather annoying noise eminating from the front of the Focus (not the passenger seat ). It's a MY2000 1.8 Zetec 3-dr

It's a rhythmic creaking noise and only apparent under braking at slow speed and seems to come from underneath the front.

It never occurs when reversing - only when the front end is loaded under braking.

Initially I suspected a bit of dirt between pad and disc (building site close by and road covered in filth) but I've had them stripped down and cleaned up, with nothing to be seen, which moved me onto bushes. I've been told these are fine - other than the anti-roll bar link mentioned below.

Since Novemeber 2010 it has had 4x wheel bearings, front discs & pads and last week had an anti-roll bar link replaced prior to MOT, which it sailed through.

It's got just over 81k on it and this noise

Any ideas of where to start looking next / solution to the problem? I've seen mention of strut top-mount bearings on t'internet.

The most frustrating thing is that at all other times the car is perfect, it drives and rides fantastically and other than wind noise, in silence.

Cheers in advance.

Andy