Trying to save data into a custom post type

Hi, thank you for your plugin.

I would like to use it to build a form where a user can type his address and the latitude and longitude are saved into a custom post field that will create a new marker with all the information into a Google Map plugin.
I’m using the plugin ‘Post My CF7 Form’ to save the form data into the custom post but my problem is that when I have to select the fields available in the form I only see ‘location’ and not all the other tags like cf7-location-lng’ and ‘cf7-location-lat’ so I don’t know how to access to the latitude and longitude.
Any idea?
Is there a way to save latitude and longitude into hidden fields?

Thank you very much