diff --git a/user_guide/installation/upgrade_200.html b/user_guide/installation/upgrade_200.html
index 58ed6e5..fa57dfb 100644
--- a/user_guide/installation/upgrade_200.html
+++ b/user_guide/installation/upgrade_200.html
@@ -102,7 +102,11 @@
 
 </p>
 
-<h2>Step 5: Update your user guide</h2>
+<h2>Step 5: Update Class extension</h2>
+<p>All core classes are now prefixed with <kbd>CI_</kbd>.  Update Models and Controllers to extend CI_Model and CI_Controller, respectively.</p> 
+
+
+<h2>Step 6: Update your user guide</h2>
 <p>Please replace your local copy of the user guide with the new version, including the image files.</p>
 
 </div>
diff --git a/user_guide/installation/upgrading.html b/user_guide/installation/upgrading.html
index 6df93b1..eb1cd9d 100644
--- a/user_guide/installation/upgrading.html
+++ b/user_guide/installation/upgrading.html
@@ -60,6 +60,7 @@
 <p>Please read the upgrade notes corresponding to the version you are upgrading from.</p>
 
 <ul>
+<li><a href="upgrade_200.html">Upgrading from 1.7.2 to 2.0</a></li>
 <li><a href="upgrade_172.html">Upgrading from 1.7.1 to 1.7.2</a></li>
 <li><a href="upgrade_171.html">Upgrading from 1.7.0 to 1.7.1</a></li>
 <li><a href="upgrade_170.html">Upgrading from 1.6.3 to 1.7.0</a></li>