diff --git a/mode/perl.py b/mode/perl.py
index 072080d..8895b33 100644
--- a/mode/perl.py
+++ b/mode/perl.py
@@ -451,9 +451,9 @@ class PerlWhichFunction(Method):
 
 class PerlHashCleanup(Method):
     '''Correctly align assignment blocks and literal hashes'''
-    def _execute(self, window, **vargs):
-        cursor = window.logical_cursor()
-        b = window.buffer
+    def _execute(self, w, **vargs):
+        cursor = w.logical_cursor()
+        b = w.buffer
 
         # so this is where we will store the groups that we find
         groups_by_line = {}
@@ -520,9 +520,12 @@ class PerlHashCleanup(Method):
 
         # remove the old text and add the new
         start_p = Point(0, start)
-        end_p = Point(0, end + 1)
-        window.kill(start_p, end_p)
-        window.insert_string(start_p, data)
+        if end < len(w.buffer.lines) - 1:
+            end_p = Point(0, end + 1)
+        else:
+            end_p = Point(len(w.buffer.lines[end]), end)
+        w.kill(start_p, end_p)
+        w.insert_string(start_p, data)
 
 class PerlWrapLine(Method):
     '''Wrap Comments and POD'''