Well got it today and it took me all of five minutes to install.
Truly plug and play. Disregard the extension as that is an adapter for the factory Bluetooth module.
No code to enter. Works like a charm. Haven't had a chance to play with it too much but will post some pics but app like Waze and Amazon Music and what not work well. The shipping was a little sketchy as it was not packed with a lot of protection. One drop probably would have done it in.
This is the one bought.
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/283374390871
I went with the "G" model which is more expensive but is guaranteed to be plug and play, updateable and comes with Android Auto on the unit already.
I think the most important thing is to get the No Name model NOT DESAY if you want android auto and the ability to update the firmware.. The no name brand is the factory OEM stereo. The Desay is CarPlay only. If the price is cheap (pretty much anything under $200 is suspect) for the 187B model it is Desay.