Alternator Compatibility 2009 vs 2010?

Does anyone know if there any differences in the alternators for a 2010 Legacy vs a 2009 Legacy? They are different part numbers at the local parts store but the pictures look identical.

We have a local u-pull-it yard here and I picked up a spare alternator for my 09 GT yesterday since the charge light lit up briefly yesterday. It came out of an 05 Outback NA but the part number between the 05-09 and the GT vs NA are the same. It was only $23 and has a 30 day warranty. I am leaning towards this alternator not being good since it makes a tick noise on each revolution. I'll stop at the local auto parts place on the way home and have them test it out. Now, the reason for my question above...This is the only Legacy/Outback 05-09 in the yard so if it needs go back they will replace it but since there are no other donor vehicles of the same year I'm not sure what they can do. They do have a 2010 Legacy NA though. Maybe one for a 2008 Impreza or 2010 Forester might work - ?

Poked around on rockauto a little just now, and for what it's worth..

'09 LGT alternator is listed at 110amps

2008 impreza non-turbo replacement alternators are listed at 90amps

2008 turbo impreza has a 110amp alternator, but "clock" is listed at 11:00 instead of 10:30 for the LGT? I don't know what that means.

2010 forester non-turbo 90amps too

2010 legacy is 110amps, but has a 6 groove pulley compared to the 5 groove on the '09.

Thanks for the info guys.

The 'clock' position I am pretty sure is the orientation of the regulator plug and/or the output terminal in relation to the mounting holes. 10:30 vs 11:00 is a pretty small difference so likely either one would work.

Makes sense now why the 2010 is a diff part number due to the different belt setup. The alternator is likely the same and the pulley could be changed to make it work if really necessary.

Yesterday after work I took the yard pull $23 alternator to the local auto parts place and they tested it. They said it checks out just fine. I also fixed the other ~2mo old alternator that I blame myself for wrecking the output stub on by not having the connector nut tight enough. Two spares sitting on the shelf for us now.