diff --git a/fcl/gen/other/proddiphoton_0.03GeV_base.fcl b/fcl/gen/other/proddiphoton_0.03GeV_base.fcl
index 8c879698a..c854d4651 100644
--- a/fcl/gen/other/proddiphoton_0.03GeV_base.fcl
+++ b/fcl/gen/other/proddiphoton_0.03GeV_base.fcl
@@ -84,8 +84,8 @@ physics.producers.generator.SigmaY: [ 116.5 ]      # y = (-116.5, 116.5)
 physics.producers.generator.SigmaZ: [ 518.5 ]      # z = (0, 1037)
 physics.producers.generator.PDist:  "histograms"     # Read a histogram
 #physics.producers.generator.HistogramFile:  "./g4numi_histOutput_zlt40m.root"     # Read a histogram
-physics.producers.generator.HistogramFile:  "/pnfs/uboone/resilient/users/klin/heavyQCDaxion_sim/fluxhist/g4numiFHCnm_histOutput_zlt40m.root"
-physics.producers.generator.PHist:  ["EAtub"]     # Read a histogram, unit in GeV
+physics.producers.generator.HistogramFile:  "g4numiFHCnm_histOutput_zlt40m.root" # This file can be found at /pnfs/uboone/persistent/resilient/users/klin/heavyQCDaxion_sim/fluxhist
+physics.producers.generator.PHist:  ["EAtub"]     # Read a histogram, unit in GeV note that value is referred to energy
 #physics.producers.generator.P0: [ 1.0  ]           # 0.53+-0.52 GeV
 #physics.producers.generator.SigmaP: [ 9.87 ]
 physics.producers.generator.AngleDist: "histograms"          # Flat angle dist.
@@ -103,3 +103,5 @@ physics.producers.generator.Theta0XZEXT:                  [180]
 physics.producers.generator.SigmaTheta0XZEXT:             [180]
 physics.producers.generator.Theta0YZEXT:            [0]
 physics.producers.generator.SigmaTheta0YZEXT:       [90]
+
+#physics.producers.generator.MaxFluxFileMB:0 # This line don't work now; a configuration useful to add.
diff --git a/fcl/gen/other/twobodydecay_overlay_gen_SimInfoMixer_prod.fcl b/fcl/gen/other/twobodydecay_overlay_gen_SimInfoMixer_prod.fcl
new file mode 100644
index 000000000..8ae5c2f59
--- /dev/null
+++ b/fcl/gen/other/twobodydecay_overlay_gen_SimInfoMixer_prod.fcl
@@ -0,0 +1,67 @@
+#include "time_memory_tracker_microboone.fcl"
+#include "services_microboone.fcl"
+#include "genie_microboone_default+MEC.fcl"
+
+#include "microboone_siminfomixer.fcl"
+#include "local_gen_include.fcl"
+
+#Keng: use this to prepare overlayed sample.
+
+services:
+{
+  scheduler:    { defaultExceptions: false }    # Make all uncaught exceptions fatal.
+  # Load the service that manages root files for histograms.
+  TFileService: { fileName: "gen_hist.root" }
+  TimeTracker:             @local::microboone_time_tracker
+  MemoryTracker:           @local::microboone_memory_tracker
+  RandomNumberGenerator: {} #ART native random number generator
+  FileCatalogMetadata:  @local::art_file_catalog_mc
+  @table::microboone_g4_services
+}
+
+process_name : SimInfoMixer      #The process name must NOT contain any underscores
+
+source:
+{
+  module_type: RootInput
+  saveMemoryObjectThreshold: 0
+  maxEvents: -1
+}
+
+outputs: {
+  out: { module_type: RootOutput
+  	 fileName: "%ifb_%tc_simmxd.root"
+	 compressionLevel: 1 
+	 dataTier: "generated"
+         SelectEvents: ["mixer_path"]
+       }
+}
+
+physics: {
+
+  producers : {
+  }
+
+  analyzers: {
+  }
+
+  filters : {
+    generator: @local::microboone_siminfomixer
+  }
+
+  mixer_path : [ generator ]
+  trigger_paths : [ mixer_path ]
+
+  output : [ out ]
+  end_paths: [ output ]
+
+}
+
+physics.filters.generator.SimInputFileNames : [ "genfile.root.local" ]
+physics.filters.generator.MCTruthInputModuleLabels: ["generator::TwoBodyDecayGen"]
+physics.filters.generator.MCFluxInputModuleLabels: ["generator::TwoBodyDecayGen"]
+physics.filters.generator.GTruthInputModuleLabels: ["generator::TwoBodyDecayGen"]
+physics.filters.generator.BeamGateInputModuleLabels: ["generator::TwoBodyDecayGen"]
+physics.filters.generator.MCTruthMCFluxAssnsInputModuleLabels: ["generator::TwoBodyDecayGen"]
+physics.filters.generator.MCTruthGTruthAssnsInputModuleLabels: ["generator::TwoBodyDecayGen"]
+physics.filters.generator.POTSummaryTag: "potinevent:SubRunPOT"