Fiat speed sensor??

[beemerdevil]

Hi guys ..... I have a Fiat Punto SX60 selecta (auto) Mk1, '99, (no i dont drive it!! - lol) and the speedo stopped working a few weeks ago.  Ive been trying to locate the speed sensor, as Ive been told this is the problem, but can i find it ?? ....NO, lol - have been on a Fiat forum but not a great deal of joy, so I thought maybe one of you fellow oofers might have an idea - i was told it was down the back of g/box, near where diff bolts on - i cannot see anything in that area, and it doesnt have ABS so not on wheels - if anyone can shed some light?? i would be eternally grateful  TIA