Yeah, I have these, which I want to have the icon:
<a href="myfile.pdf">PDF Version of this Report</a>
And these, which I don't:
<a href="tnmap.pdf"><img src="tnmap.jpg" alt="Tennessee Map" /></a>
I think I can't select a parent tag of a child, so I'll probably have to use a class for those. But with around 30,000 PDF links and only a few dozen being images, I think that's not a bad trade-off. Better than having to add a class to them all.