I have been attempting to cure an inoperative horn fault and have traced it to a possible relay fault but I am unable to locate the relay position, any ideas ?

The horn relay for the legacy is up the left of the driver's area.

 

You can see it in this scan.

http://www.surrealmirage.com/subaru/files/swap/elect_unit_loc/6-3_electrical_unit_location03.jpg

 

I think the pic got cut off, I'll be hopefully getting an updated pic online.

 

Also, just an fyi. I've got scans for all the electrical unit/relay locations on my swap page. Yes they are for the legacy, but should be similar for other models and years.

Thanks, that gives me somewhere to look.