I love the customizable charging dock from erisko and modified the base to have some holes for cable ties to connect them to regular grills in the car.
You need these two parts from his design:
This thing only replaces the standing dock with one that can be connected to the car! Read his instructions carefully to customize it so that it fits your phone.
If you want to get rid of the slope of the connector adapter, you can change the MobileHolderV6.scad file by removing these lines in the module connector()
Filament: Procatec PETG navy