Hi Jason,
My name's Bagus, an expert in Web Developments & Modifications. Thank you for posting the project.
I understand that you want to have a functionality in your Wordpress site of user entering their postal codes, then we store the data, manipulating it via Google Geocoding API, and display it via Google javascript API.
Yes, I can make it work for you.
If you want to know me more, you can open my Profile page
(including awards & honorable certification / skill test result)
Let me know your thought. There is a chat button near my name so we can start discussing.
Regards,
Bagus.