Hi Keith,
Welcome to the forum!
Here's a download link to the version for your Streets & Trips 2006:
STkeys_v106.exe . Save it to your desktop and run it. When both programs, S&T 2006 and S&T Keys, are running, press F1-key on your keyboard to view a list of hotkeys available in S&T Keys version 1.06. That was one of the early versions, and it doesn't do much in comparison to S&T Keys version 2.0 and newer. But it does work, and many people are still using it.
Enjoy!