I've searched and searched but I can't find any guides or hints.

Tried this morning, I only managed to break a peice of the battery tray off after having a rage on, nevermind get it off!

Need to fix my starter signal wire...

Do I remove the battery tray first?? There are loads of wires, do I have to disconnect all of those?

http://www.google.co.uk/search?q=remove+battery+fabia+vrs&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-GB:official&client=firefox-a

what does the starter signal wire look like or come from?

Need to this myself.

what does the starter signal wire look like or come from?

Need to this myself.

Haven't a clue yet, but I'll take a picture when fixing it!!

Tried this morning, I only managed to break a peice of the battery tray off after having a rage on, nevermind get it off!

Need to fix my starter signal wire...

Do I remove the battery tray first?? There are loads of wires, do I have to disconnect all of those?

Don't know the answer to your latter questions, but I at least have now managed to release all three clips for the cage - you need to feed a lever down each to release. Difficult to describe - you'll find out by experience. The one on the left is easiest - after taking off the air intake. The one on the right isn't difficult either. The one at the back is worse.

I haven't yet tried disconnecting the two main leads to see what else might have to move.

Fixed mine today, you can push the 2 blocks attached to the top of the tray to the RIGHT, then you can lift them off (with force)...

Then remove the nut at the front of the battery - remove battery.

Then pretty straight forward... remove the bolts (approx 3) for the battery tray.