I am not great with projections and I have some data I need to correct. I am doing work for St. Kitts and Nevis (Caribbean) and the data I got from them has a custom projection. I asked them for information on it to try to convert it back to something mainstream so I can then use ArcMap to then transform it and was told the custom projection was WGS 1984.
I then converted some lat / long data into decimal degrees and added it to the map. The resulting points were almost 2 million metres off. This figure correlates to the massive extent range that the custom projection has (pic attached). Also, the custom projection shows a GCS of "GCS_North_American_1983", which does not match what they told me.
I have been attempting to fix this for days now by reading others questions, so any help would be appreciated.