diff --git a/Validation/offSpill.fcl b/Validation/offSpill.fcl
index 8493bdd6..e6ae8129 100644
--- a/Validation/offSpill.fcl
+++ b/Validation/offSpill.fcl
@@ -48,3 +48,14 @@ source.maxEvents : 10000
 services.scheduler.wantSummary: true
 services.TimeTracker.printSummary: true
 services.TFileService.fileName : "/dev/null"
+#
+# run the CentralHelix fit, extension and CRV extrapolation with BField correction, using the KinKal domain-walk
+# stability controls; bfgeom_v01_minfield is the stock v01 map with bfield.minUsableField 1e-6 T
+#
+physics.producers.KKCHmu.FitSettings.BFieldCorrection        : true
+physics.producers.KKCHmu.ExtensionSettings.BFieldCorrection  : true
+physics.producers.KKCHmu.FitSettings.MinDomainTimeStep       : 0.03
+physics.producers.KKCHmu.ExtensionSettings.MinDomainTimeStep : 0.03
+physics.producers.KKCHmu.FitSettings.DomainMargin            : 0.0
+physics.producers.KKCHmu.ExtensionSettings.DomainMargin      : 0.0
+services.GeometryService.bFieldFile : "Offline/Mu2eG4/geom/bfgeom_v01_minfield.txt"