You can get most of the data you need thorugh the OBD2 port, located on the lower part of the dash on the drivers side. It is a known and documented protocol. F

You can get most of the data you need thorugh the OBD2 port, located on the lower part of the dash on the drivers side. It is a known and documented protocol. From there, you can then maybe get some sort of LED based display bright enough to show up on your windshield. Again, this stuff is mainstream. Best of all, you can do it with an arduino.