Two Guys posted a comment on discussion Tutorials and How-Tos

This was actually developed using a Raspberry Pi running FreePBX and Asterisk, in case anyone has a spare OBi200 or OBi202 lying about. How to use an Obihai 200 series VoIP device as a gateway between Google Voice and FreePBX https://twosortoftechguys.wordpress.com/2018/12/05/how-to-use-an-obihai-200-series-voip-device-as-a-gateway-between-google-voice-and-freepbx/