If you start with a survey in local (like 5000/5000) / State Plane / UTM coordinates that don't match your GPS/GNSS CRS, and you want to keep the survey where it is plus use GPS/GNSS, you can. See Calibrating GPS/GNSS to Your Survey.
Site Calibration
TPC's Site Calibration lets you easily work with GPS/GNSS in your survey. GPS/GNSS geodetic positions are automatically calibrated to your survey's CRS and any survey points export out to GPS/GNSS are automatically reverse calibrated back to the BPS/GNSS CRS.
