mine leaks too - its a '99 DII 135k miles
I replaced the rear output seal which stopped one leak and now have a couple more to tackle using "Hylomar" gasket stuff from Atlantic British (about $10) - the rear seal was just a few bucks from Nathan at Discount Rovers.
My recommendation is if it is leaking and you can't tell exactly where (like me) just replace every seal you can in and around the leak area. Be thorough and take your time and hopefully the leak won't come back - at least for a while anyway.