Re-establish ground control in MGA Zone 50 with RTK average Horizontal and Vertical from original SSM marks. Re-apply the Hill 50 Plane Grid following the methodology of the originating survey, creating a Localisation file. Acquire a Localisation conversion from Carlson SurvCE .LOC to Trimble .DC Re-setup Trimble Base Station with new MGA coordinates and apply DC file. Field checks with a Trimble instrument to ensure accuracy. Supply .LOC file for Topcon Drill Rig Machine Guidance.