diff --git a/app/assets/javascripts/application.js b/app/assets/javascripts/application.js
index fc6dece59..83ae86502 100644
--- a/app/assets/javascripts/application.js
+++ b/app/assets/javascripts/application.js
@@ -10,10 +10,3 @@
 //= require govuk_publishing_components/components/step-by-step-nav
 
 //= require_tree ./modules
-//= require set-ga-client-id-on-form
-
-var form = document.querySelector('.js-service-sign-in-form')
-
-if (form) {
-  new GOVUK.SetGaClientIdOnForm(form) // eslint-disable-line no-new
-}
diff --git a/app/assets/javascripts/modules/set-ga-client-id-on-form.js b/app/assets/javascripts/modules/set-ga-client-id-on-form.js
new file mode 100644
index 000000000..250777bb7
--- /dev/null
+++ b/app/assets/javascripts/modules/set-ga-client-id-on-form.js
@@ -0,0 +1,19 @@
+window.GOVUK = window.GOVUK || {}
+window.GOVUK.Modules = window.GOVUK.Modules || {};
+
+(function (Modules) {
+  function SetGaClientIdOnForm ($module) {
+    this.$module = $module
+  }
+
+  SetGaClientIdOnForm.prototype.init = function () {
+    var form = this.$module
+    window.ga(function (tracker) {
+      var clientId = tracker.get('clientId')
+      var action = form.getAttribute('action')
+      form.setAttribute('action', action + '?_ga=' + clientId)
+    })
+  }
+
+  Modules.SetGaClientIdOnForm = SetGaClientIdOnForm
+})(window.GOVUK.Modules)
diff --git a/app/assets/javascripts/set-ga-client-id-on-form.js b/app/assets/javascripts/set-ga-client-id-on-form.js
deleted file mode 100644
index dd61d789b..000000000
--- a/app/assets/javascripts/set-ga-client-id-on-form.js
+++ /dev/null
@@ -1,18 +0,0 @@
-(function () {
-  'use strict'
-
-  window.GOVUK = window.GOVUK || {}
-  var GOVUK = window.GOVUK
-
-  function SetGaClientIdOnForm (form) {
-    if (!form || !window.ga) { return }
-
-    window.ga(function (tracker) {
-      var clientId = tracker.get('clientId')
-      var action = form.getAttribute('action')
-      form.setAttribute('action', action + '?_ga=' + clientId)
-    })
-  }
-
-  GOVUK.SetGaClientIdOnForm = SetGaClientIdOnForm
-})(window, window.GOVUK)
diff --git a/app/views/content_items/service_sign_in/_choose_sign_in.html.erb b/app/views/content_items/service_sign_in/_choose_sign_in.html.erb
index af9ddc701..58245b984 100644
--- a/app/views/content_items/service_sign_in/_choose_sign_in.html.erb
+++ b/app/views/content_items/service_sign_in/_choose_sign_in.html.erb
@@ -14,15 +14,14 @@
   </div>
 <% end %>
 <%
-  data_attrs = { module: "track-radio-group" }
+  data_attrs = { module: "track-radio-group set-ga-client-id-on-form" }
   data_attrs["tracking-code"] = @content_item.tracking_code if @content_item.tracking_code
   data_attrs["tracking-domain"] = @content_item.tracking_domain if @content_item.tracking_domain
   data_attrs["tracking-name"] = @content_item.tracking_name if @content_item.tracking_name
 %>
 <%= form_tag({controller: 'content_items', action: 'service_sign_in_options'},
              method: "post",
-             data: data_attrs,
-             class: 'js-service-sign-in-form') do %>
+             data: data_attrs) do %>
   <% legend_text = render 'govuk_publishing_components/components/title', title: @content_item.title %>
   <%= render "govuk_publishing_components/components/fieldset", legend_text: legend_text do %>
     <div class="govuk-grid-row">
diff --git a/spec/javascripts/set-ga-client-id-on-form.spec.js b/spec/javascripts/set-ga-client-id-on-form.spec.js
index b6c6c8718..69272fefa 100644
--- a/spec/javascripts/set-ga-client-id-on-form.spec.js
+++ b/spec/javascripts/set-ga-client-id-on-form.spec.js
@@ -8,10 +8,9 @@ describe('SetGaClientIdOnForm', function () {
   var form
 
   beforeEach(function () {
-    form = $(
-      '<form class="js-service-sign-in-form" action="/endpoint"></form>'
-    )
-    new GOVUK.SetGaClientIdOnForm(form[0]) // eslint-disable-line no-new
+    form = $('<form action="/endpoint"></form>')
+    var setId = new GOVUK.Modules.SetGaClientIdOnForm(form[0])
+    setId.init()
   })
 
   it('sets the _ga client id as a query param on the form action', function () {
diff --git a/test/integration/service_sign_in/choose_sign_in_test.rb b/test/integration/service_sign_in/choose_sign_in_test.rb
index ea6561dca..e09b24bbc 100644
--- a/test/integration/service_sign_in/choose_sign_in_test.rb
+++ b/test/integration/service_sign_in/choose_sign_in_test.rb
@@ -20,7 +20,7 @@ class ChooseSignInTest < ActionDispatch::IntegrationTest
       assert_not page.has_css?("#proposition-menu")
 
       assert page.has_css?('.gem-c-back-link[href="/log-in-file-self-assessment-tax-return"]', text: "Back")
-      assert page.has_css?('form[data-module="track-radio-group"]')
+      assert page.has_css?('form[data-module="track-radio-group set-ga-client-id-on-form"]')
       assert page.has_css?("form[data-tracking-code='UA-xxxxxx']")
       assert page.has_css?("form[data-tracking-domain='tax.service.gov.uk']")
       assert page.has_css?("form[data-tracking-name='somethingClicky']")