i done colored them red..hehe its crude...my photoshop is not installed at the moment but you get the idea.
in the section of the service manual that shows you how to change the timing belt there is a detailed picture of what each pully looks like, in this pic they just show where they are.
IIRC one of those pullyes supports more of a load than the other... one is 'beefier' then the other...I dont remember what one goes where...but like I said if you can get the other pic of the timing belt install...you can clearly see what one goes where...
if i still worked for subaru I might be able to help you better...but I dont so this is all I can offer, hope it helps
Jay