I have done a bit of reading on Arduino GPS shields and related software libraries. There is not much you would have to do other than hook everything together. With some of the GPS units you give them the coordinates of your waypoint or destination and it spits back your course, heading, ground speed, and estimated time remaining. So all you would have to do would be display the data in the desired format. I also see that the best choice for the display would be a transflective LCD. This will work in bright sunlight and most of them have a backlight that can be turned on in dim light. There are even some transflective graphics displays, if you want to get extravagant.