Here's something interesting: An open source SSM software with versiosn for windows and linux. It seems to be for early OBD2 Subarus. They say
Legacy/Liberty, Outback, Baja, Impreza, Forester and Tribeca (not before MY1999). But it must be worth trying it with a 97 SVX.
The screenshots show it can read an OBD1 TCU. So we might even be able to do something with it on the OBD1 cars.
http://developer.berlios.de/projects/freessm/
__________________
Subaru ECU and TCU Website
1992 Alcyone SVX Version L
1992 Alcyone SVX Version L
1994 Alcyone SVX S40-II
2004 Subaru Legacy 2.5 SE Sports Tourer
1996 Subaru Legacy 2.2 GX Wagon
1988 Subaru Justy J12 SL-II