GPS data imported to incorrect Coordinate System

[JamesLandwehr]

We had another department import their point data into a feature class with a different coordinate system (NAD27) than the data was collected in. Now it seems we can't get the data correctly georeferenced. Of course, the data was deleted from the collector before we could check it for spatial reference. My question is, is there a way to salvage the data that was incorrectly imported? The data was collected in GCS WGS84, and we need it in NAD27 SPCS WI South Zone US Feet. Any help appreciated.

[JimCousins]

If I understand correctly, the points were assigned an incorrect coordinate system. If you simply redefine the coordinate system correctly (GCS WGS84), next you can reproject it to get a copy in SP WI south NAD27 feet.
ArcToolbox >> Data Management Tools >> Projections and Transformations >> Define Projection
ArcToolbox >> Data Management Tools >> Projections and Transformations >> Feature >> Project
Best Regards,
Jim