So I upgraded to a pi3, mainly because of the inbuilt wifi and Bluetooth. I'm told I can still use a dongle to extend the wifi signal but I'll see how that pans out once I've fitted it back to the car after I've set it all up.
still need to purchase a good gps antenna and also find suitable software.
any tips on a GUI maker? I'm new to GUIs, so any tips out there would be fab....