It's been a LONG time since I've had the headlight motor assembly apart on one of these... You'll find Toyota's information on testing the retractor control system and motor here:
http://www.cygnusx1.net/Supra/Librar...aspx?S=BE&P=23
Failing that you may just need to disconnect the rotating lever between the armature and headlight motor and clock it 180?.
I think this has been discussed here in the past, but it's not a common issue. You may want to try digging a little in the MKIII section to see if you can find any other threads on the matter.