diff --git a/examples/cluster.c b/examples/cluster.c
index f6f99ed..b9c8b53 100644
--- a/examples/cluster.c
+++ b/examples/cluster.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdarg.h>
 #include <string.h>
 #include <math.h>
 
@@ -9,7 +10,7 @@
 #include <hexagram/window.h>
 
 typedef struct _hexagram_cluster_state {
-    double rpm, rps, temp, level;
+    double rpm, rps, temp, fuel;
 } hexagram_cluster_state;
 
 static hexagram_cluster_state state = {
@@ -328,7 +329,7 @@ static void cluster_update(struct can_frame *frame) {
         }
 
         case 0x320: {
-            state.level = (double)(frame->data[2]);
+            state.fuel = (double)(frame->data[2] & 0xf) / 16.0;
 
             break;
         }
@@ -368,7 +369,22 @@ static void cluster_draw(cairo_t *cr,
                            width  * 0.57,
                            height * 0.76,
                            height * 0.11,
-                           0.5);
+                           state.fuel);
+}
+
+static int usage(int argc, char **argv, const char *message, ...) {
+    if (message) {
+        va_list args;
+
+        va_start(args, message);
+        vfprintf(stderr, message, args);
+         fprintf(stderr, "\n");
+        va_end(args);
+    }
+
+    fprintf(stderr, "usage: %s canif\n", argv[0]);
+
+    return 1;
 }
 
 int main(int argc, char **argv) {
@@ -389,11 +405,17 @@ int main(int argc, char **argv) {
 
     cairo_t *fg, *bg;
 
-    if ((can_if = hexagram_can_if_open("vcan0")) == NULL)
-        exit(1);
+    if (argc != 2) {
+        return usage(argc, argv, "No CAN interface specified");
+    }
 
-    if ((window = hexagram_window_new_x11(NULL, width, height)) == NULL)
-        exit(1);
+    if ((can_if = hexagram_can_if_open(argv[1])) == NULL) {
+        return 1;
+    }
+
+    if ((window = hexagram_window_new_x11(NULL, width, height)) == NULL) {
+        return 1;
+    }
 
     display = hexagram_window_display(window);
 
diff --git a/examples/view.c b/examples/view.c
index 3678c5e..8d84417 100644
--- a/examples/view.c
+++ b/examples/view.c
@@ -15,6 +15,7 @@ static int usage(int argc, char **argv, const char *message, ...) {
 
         va_start(args, message);
         vfprintf(stderr, message, args);
+         fprintf(stderr, "\n");
         va_end(args);
     }
 
@@ -57,17 +58,17 @@ int main(int argc, char **argv) {
 
             wprintw(win, "%6.1lf RPM", rpm);
         } else if (frame.can_id == 0x540) {
-            wmove(win, 6, 0);
+            wmove(win, 7, 0);
 
             if ((frame.data[7] & 0xc) == 0xc) {
                 uint8_t gear = ((frame.data[7] & 0xf0) >> 4) - 2;
 
                 wprintw(win, "1 2 3 4 5 6");
 
-                wmove(win, 7, 0);
+                wmove(win, 8, 0);
                 wprintw(win, "                   ");
 
-                wmove(win, 7, gear * 2);
+                wmove(win, 8, gear * 2);
 
                 wprintw(win, "_");
             } else {
@@ -75,10 +76,10 @@ int main(int argc, char **argv) {
 
                 wprintw(win, "P R N D S  ");
 
-                wmove(win, 7, 0);
+                wmove(win, 8, 0);
                 wprintw(win, "                   ");
 
-                wmove(win, 7, pos * 2);
+                wmove(win, 8, pos * 2);
 
                 wprintw(win, "_");
             }
@@ -104,8 +105,11 @@ int main(int argc, char **argv) {
             wmove(win, 3, 0);
 
             wprintw(win, "%6.1lf °C ambient", temp);
-        } else if (frame.can_id == 0x4a0) {
-            
+        } else if (frame.can_id == 0x320) {
+            double fuel = (double)(frame.data[2] & 0xf) / 16.0;
+
+            wmove(win, 5, 0);
+            wprintw(win, "%5.0lf%% Fuel", fuel * 100.0);
         }
 
         if (((now.tv_sec * 1000000) + now.tv_usec) - ((last.tv_sec * 1000000) + last.tv_usec) > 100000) {