If you have the Factory Service Manual, check the Scheduled Maintenance section.
Can't tell you exactly where the drain plug is on the 470. The fill (at least with the 450) is via the tranny fluid dip stick tube.
'97 LX 450: Slee sliders, rear bumper/tire carrier, tcase skidplate, ARB front bumper, OME, LEDs, yada, yada, yada
'97 LX 450 (hers): stock