I don't have a record of what they were before, sorry; but I do know that if I plug the router into the Test Socket the Downstream Speed gets to 2048 kbps.
So there's something with your extension wiring.
I have panicked and just ordered a BT I-Plate!
That wont fix your wiring.
Can you post a picture on an image-hosting website, eg http://imageshack.us
showing what you've changed and put a link here?
Or describe what colours are attached to which number pins?