Drain plug in TC was eliminated in April 99.
Sorry I don't know the crankshaft nut size off hand but...
If you have the car on jack stands, turning the TC is easy. I just inserted a screwdriver (old one) into the 'window' in the TC frame and turned the TC drum a little at a time until drain plug showed up.
FYI - For some reason the seals under the drain plugs are different part numbers although the drain plugs are same size.
If you haven't done a 722.6 before, it's a good idea to calibrate an old 1 gal milk bottle in quarts. Then measure the amount you drain out (between 7-8 qts) and put the same amount back in. That way you can drive the car to warm up the transmission before setting the final level.