diff --git a/gds/user_id_programming.gds b/gds/user_id_programming.gds
index 985e095..c5f3ff0 100644
--- a/gds/user_id_programming.gds
+++ b/gds/user_id_programming.gds
Binary files differ
diff --git a/mag/user_id_programming.mag b/mag/user_id_programming.mag
index 5b9cb1b..df478ad 100644
--- a/mag/user_id_programming.mag
+++ b/mag/user_id_programming.mag
@@ -3154,7 +3154,6 @@
 port 34 nsew
 << properties >>
 string FIXED_BBOX 0 0 7109 7077
-string GDS_FILE /project/openlane/user_id_programming/runs/user_id_programming/results/magic/user_id_programming.gds
-string GDS_START 24124
-string GDS_END 90784
+string GDS_FILE ../gds/user_id_programming.gds
+string GDS_START 0
 << end >>
diff --git a/scripts/set_user_id.py b/scripts/set_user_id.py
new file mode 100755
index 0000000..87fdd9e
--- /dev/null
+++ b/scripts/set_user_id.py
@@ -0,0 +1,209 @@
+#!/bin/env python3
+#
+# set_user_id.py ---
+#
+# Manipulate the magic database, GDS, and verilog source files for the
+# user_id_programming block to set the user ID number.
+#
+# The user ID number is a 32-bit value that is passed to this routine
+# as an integer.
+#
+# user_id_programming layout map:
+# Positions marked (in microns) for value = 0.  For value = 1, move
+# the via 0.92um to the left.
+#
+# Layout grid is 0.46um x 0.34um with half-pitch offset (0.23um, 0.17um)
+#
+# Signal        Via position (um)
+# name		X      Y     
+#--------------------------------
+# mask_rev[0]   14.49  9.35
+# mask_rev[1]	16.33  9.35
+# mask_rev[2]	10.35 20.23
+# mask_rev[3]	 8.05  9.35
+# mask_rev[4]	28.29  9.35
+# mask_rev[5]	21.85 25.67
+# mask_rev[6]	 8.05 20.23
+# mask_rev[7]   20.47  9.35
+# mask_rev[8]   17.25 17.85
+# mask_rev[9]   25.53 12.07
+# mask_rev[10]  22.31 20.23
+# mask_rev[11]  13.11  9.35
+# mask_rev[12]	23.69 23.29
+# mask_rev[13]	24.15 12.07
+# mask_rev[14]	13.57 17.85
+# mask_rev[15]	23.23  6.97
+# mask_rev[16]	24.15 17.85
+# mask_rev[17]	 8.51 17.85
+# mask_rev[18]	23.69 20.23
+# mask_rev[19]	10.81 23.29
+# mask_rev[20]	14.95  6.97
+# mask_rev[21]	18.17 23.29
+# mask_rev[22]	21.39 17.85
+# mask_rev[23]	26.45 25.67
+# mask_rev[24]	 9.89 17.85
+# mask_rev[25]	15.87 17.85
+# mask_rev[26]	26.45 17.85
+# mask_rev[27]	 8.51  6.97
+# mask_rev[28]	10.81  9.35
+# mask_rev[29]	27.83 20.23
+# mask_rev[30]	16.33 23.29
+# mask_rev[31]	 8.05 14.79
+#--------------------------------
+
+import os
+import sys
+import re
+
+def usage():
+    print("set_user_id.py <user_id_value> [<path_to_project>]")
+    return 0
+
+if __name__ == '__main__':
+
+    # Coordinate pairs in microns for the zero position on each bit
+    mask_rev = (
+	(14.49,  9.35), (16.33,  9.35), (10.35, 20.23), ( 8.05,  9.35),
+	(28.29,  9.35), (21.85, 25.67), ( 8.05, 20.23), (20.47,  9.35),
+	(17.25, 17.85), (25.53, 12.07), (22.31, 20.23), (13.11,  9.35),
+	(23.69, 23.29), (24.15, 12.07), (13.57, 17.85), (23.23,  6.97),
+	(24.15, 17.85), ( 8.51, 17.85), (23.69, 20.23), (10.81, 23.29),
+	(14.95,  6.97), (18.17, 23.29), (21.39, 17.85), (26.45, 25.67),
+	( 9.89, 17.85), (15.87, 17.85), (26.45, 17.85), ( 8.51,  6.97),
+	(10.81,  9.35), (27.83, 20.23), (16.33, 23.29), ( 8.05, 14.79));
+
+    optionlist = []
+    arguments = []
+
+    debugmode = False
+
+    for option in sys.argv[1:]:
+        if option.find('-', 0) == 0:
+            optionlist.append(option)
+        else:
+            arguments.append(option)
+
+    if len(arguments) != 1 and len(arguments) != 2:
+        if len(arguments) != 0:
+            print("Wrong number of arguments given to cleanup_unref.py.")
+        usage()
+        sys.exit(0)
+
+    if '-debug' in optionlist:
+        debugmode = True
+
+    user_id_value = arguments[0]
+
+    # Convert to binary
+    user_id_bits = '{0:032b}'.format(int(user_id_value))
+
+    if len(arguments) == 2:
+        user_project_path = arguments[1]
+    else:
+        user_project_path = os.getcwd()
+
+    magpath = user_project_path + '/mag'
+    gdspath = user_project_path + '/gds'
+    vpath = user_project_path + '/verilog'
+    errors = 0 
+
+    if os.path.isdir(gdspath):
+
+        # Bytes leading up to via position are:
+        viarec = "00 06 0d 02 00 43 00 06 0e 02 00 2c 00 2c 10 03 "
+        viabytes = bytes.fromhex(viarec)
+
+        # Read the GDS file.  If a backup was made of the zero-value
+        # program, then use it.
+
+        gdsbak = gdspath + '/user_id_prog_zero.gds'
+        gdsfile = gdspath + '/user_id_programming.gds'
+
+        if os.path.isfile(gdsbak):
+            with open(gdsbak, 'rb') as ifile:
+                gdsdata = ifile.read()
+        else:
+            with open(gdsfile, 'rb') as ifile:
+                gdsdata = ifile.read()
+
+        for i in range(0,32):
+            # Ignore any zero bits.
+            if user_id_bits[i] == '0':
+                continue
+
+            coords = mask_rev[i]
+            xum = coords[0]
+            yum = coords[1]
+
+            # Contact is 0.17 x 0.17, so add and subtract 0.085 to get
+            # the corner positions.
+
+            xllum = xum - 0.085
+            yllum = yum - 0.085
+            xurum = xum + 0.085
+            yurum = yum + 0.085
+ 
+            # Get the 4-byte hex values for the corner coordinates
+            xllnm = round(xllum * 1000)
+            yllnm = round(yllum * 1000)
+            xllhex = '{0:08x}'.format(xllnm)
+            yllhex = '{0:08x}'.format(yllnm)
+            xurnm = round(xurum * 1000)
+            yurnm = round(yurum * 1000)
+            xurhex = '{0:08x}'.format(xurnm)
+            yurhex = '{0:08x}'.format(yurnm)
+
+            # Magic's GDS output for vias always starts at the lower left
+            # corner and goes counterclockwise, repeating the first point.
+            viaoldposdata = viarec + xllhex + yllhex + xurhex + yllhex
+            viaoldposdata += xurhex + yurhex + xllhex + yurhex + xllhex + yllhex
+            
+            # For "one" bits, the X position is moved 0.92 microns to the left
+            newxllum = xllum - 0.92
+            newxurum = xurum - 0.92
+
+            # Get the 4-byte hex values for the new corner coordinates
+            newxllnm = round(newxllum * 1000)
+            newxllhex = '{0:08x}'.format(newxllnm)
+            newxurnm = round(newxurum * 1000)
+            newxurhex = '{0:08x}'.format(newxurnm)
+
+            vianewposdata = viarec + newxllhex + yllhex + newxurhex + yllhex
+            vianewposdata += newxurhex + yurhex + newxllhex + yurhex + newxllhex + yllhex
+
+            # Diagnostic
+            if debugmode:
+                print('Bit ' + str(i) + ':')
+                print('Via position ({0:3.2f}, {1:3.2f}) to ({2:3.2f}, {3:3.2f})'.format(xllum, yllum, xurum, yurum))
+                print('Old hex string = ' + viaoldposdata)
+                print('New hex string = ' + vianewposdata)
+
+            # Convert hex strings to byte arrays
+            viaoldbytedata = bytearray.fromhex(viaoldposdata)
+            vianewbytedata = bytearray.fromhex(vianewposdata)
+
+            # Replace the old data with the new
+            if viaoldbytedata not in gdsdata:
+                print('Error: via not found for bit position ' + str(i))
+                errors += 1 
+            else:
+                gdsdata = gdsdata.replace(viaoldbytedata, vianewbytedata)
+
+        if errors == 0:
+            # Keep a copy of the original 
+            if not os.path.isfile(gdsbak):
+                os.rename(gdsfile, gdsbak)
+
+            with open(gdsfile, 'wb') as ofile:
+                ofile.write(gdsdata)
+
+            print('Done!')
+            
+        else:
+            print('There were errors in processing.  No file written.')
+            sys.exit(1)
+
+    else:
+        print('No directory ' + gdspath + ' found.')
+        sys.exit(1)
+    sys.exit(0)