I hate to say it, but that doesn't sound like a torque convertor problem. Torque convertors have a really insignificant failure rate. Unless, the convertor itself is cracked. I would suspect a front seal or some failure of the pump. Where is the fluid leak showing itself? when you put the tranny in gear, does the engine over rev, does it show any signs of engaging at all? Does it work in the reverse position?
1987 BMW 325