If you get the door card off, it is quite self explanatory, there is 3 bolts holding the glass to the mechanism, you then have to undo several other bolts to remove the regulator and the metal bar thingamybob that the glass slides up and down. You then should be able to remove the whole lot after you have unplugged it.
Its easy and can be done in 5 mins if you have done it before
http://www.toyodiy.com/parts/p_J_1993_TOYOTA_SUPRA_JZA80-ALPQZ_6704.html
p/n 69810 is the motor/regulator you need, IIRC you can change it over without taking the whole assy out but I may be wrong