Here is what I’m starting out with:

• Raspberry Pi 7″ touchscreen monitor (just ordered)
• Monitor case (just ordered)
• Raspberry Pi 3
• GlobalSat BU-353-S4 USB GPS Receiver
• USB sound card
• USB Bluetooth Dongle 4.0 EDR Receiver
• Logitech Wireless Touch Keyboard K400

Here’s a start on setting up the touchscreen monitor and a video. To flip the screen, edit /boot/config.txt and add lcd_rotate=2

Here’s a start on setting up the GPS module. Using Raspbian Jesse or later (Buster), you must disable a systemd service that gpsd installs then start gpsd:

sudo systemctl stop gpsd.socket
sudo systemctl disable gpsd.socket
sudo killall gpsd
sudo gpsd /dev/ttyUSB0 -F /var/run/gpsd.sock

Try running gpsmon, cgps -s, or xgps to get a live-streaming update of GPS data.

This video helped with “no fix”.

Here’s a start with ODB-Pi.

Here’s a start with Navit.