I don't know if it helps but I came up with a way to extract the lat and long from a web viewer set to show the address from the address fields.
In this demo it will calculate the distance between the address in the current record and other addresses in the database, showing them in a portal sorted by closest.
I use this at the start of a script to show the location of a client's address:
Clients::ClientAddressNumber & "+" & Clients::ClientAddressLine1 & "+" & Clients::ClientAddressPostCodeFull
The web viewer show the location with a map pin, and the street view on the left. The user has full interaction with the normal googlemap web page.