Hello ictsoftail, and welcome to SimV!

First, you'll need to know the actual name of the gauge responsible for the altitude callouts. Then it's just a matter of adding that gauge to the panel.cfg of your choice. (It's a bit more complicated than that really, but that's how to get started. We'll get into the trickier stuff a bit later.)
Can you post a link to the panel you're talking about?
Incidentally, you'll likely get more of the help you're looking for if you post your question in the "Scenery & Panel Design" located
here.
