is there a drain plug for a disco1 auto box, and if so- where?

the gaynes manual says to see your local stealer but i aint paying them just to drain some oil from the box (as the previous owner has overfilled it).

thanks. Mark

This could be what your after, http://photos-h.ak.fbcdn.net/photos-ak-snc1/v2735/47/91/515963368/n515963368_1607767_6516384.jpg Number 17 is the drain plug for the autobox