open google map in specific size window

I was able to create a map with a marker for the location of a business I’m doing a site for, using WordPres 2.1.3. I set a link to the map in the sidebar (inside a text box using sidebar widgets).

It works, but I’d like the map to be a popup window rather than taking the user to a totally new page that is full screen – only a portion of which is the map. I’ve tried alot of things but so far no luck.

Hoping someone has done this before.