You're good. :) We need people like you working behind the counter.
It's appalling to discover so many auto parts stores where it's hard to find a clerk (of either gender) who would recognize a ball joint... or most anything else. *sigh* Recently, when I asked which gaskets were included in a timing belt kit, the clerk hesitated, then clicked a few keys and swiveled the monitor toward me as she pointed to every single item in the picture, "It comes with that, and that, and that, and that."
- Erik