I have 3 diffs. which I am now prepared to sell if anyone is interested in one.
The first is a used, approx. 17,000 miles 3.9 lsd as fitted to 2001 Academy Cars. This is not a remanufactured diff, but an original Ford unit. I believe it is a plate type, possibly with modified ramp angles, but not sure. However, I can guarantee it is quiet and with no problems. I am looking for around £895 ono.
The second is brand new, unused and still boxed 3.6 open diff. Ideal to lower the final gearing of your Duratec car. Not remanufactured but an original Ford supplied unit. £750 ono
The third one is a used, Ford supplied 3.38 open diff. bought s/h and never been in a Seven, but thought to be good. This ratio is getting quite rare now.
I am quite happy to refund the purchase price if it turns out to be faulty. £575 ono