I am using ArcMaps 10.3 and know just enough to get into trouble. I went to upload line shape files into a Garmin Montana GPS unit (through the DNR GPS application from Minnesota DNR), and discovered that most files are projected in stereographic south pole. I didn't even know that was a projection, and have no idea how it happened, especially since we have transferred these files to the GPS before with no problems. When I checked the projections of the layers in the map I'm trying to upload, I found out that there were a combination of three GCS
