The following are scans of install manuals for an OEM rear diff protector. The first Scan is for my 1997 Legacy Outback and the second attached image is for my friends 2002 Legacy Outback. As you can see it's a lot easier to install the newer version. The price is relatively cheap for the protector, just under 60 bucks from Lisa Wilkins at Troncalli Subaru (800-334-4717). It makes a nice jacking point too.

This is for the new style Legacy I installed it on an 02' Outback

Here is a pic of the Skid plate for the 02'

I installed the plate today on Mike's Outback. It was very simple. The only hard part was getting the torque wrench on the right rear nut. It's a close fit. Other than that it was very easy. ONe strange thing, the install directions call for a 12 mm wrench. I'm not sure what that was for. All the nuts were 17mm and the two new ones were 18mm, strange. Here are some install pics.

Rear nuts.

done