Appologies where its due, that wasn't even you that said that Antony

Damn you TwinkleTwinkleLittleStar

That is the plug though yes, and thats for a fuel computer. And no there isn't the plug i was hoping for

Basically the test you want to do, is bridge the Brown/Black wire to earth, and the gauge should read a full tank, if it does, the sender is probably gone, if not, its probably the gauge