protected function getRelatedDocumentsGridField()
    {
        $gridField = GridField::create(
            'RelatedDocuments',
            _t('DMSDocument.RELATEDDOCUMENTS', 'Related Documents'),
            $this->RelatedDocuments(),
            new GridFieldConfig_RelationEditor
        );

        $gridFieldConfig = $gridField->getConfig();
        $gridFieldConfig->removeComponentsByType('GridFieldEditButton');
        $gridFieldConfig->addComponent(new DMSGridFieldEditButton(), 'GridFieldDeleteAction');

        $gridField->getConfig()->removeComponentsByType('GridFieldAddNewButton');
        // Move the autocompleter to the left
        $gridField->getConfig()->removeComponentsByType('GridFieldAddExistingAutocompleter');
        $gridField->getConfig()->addComponent(
            $addExisting = new GridFieldAddExistingAutocompleter('buttons-before-left')
        );

        // Ensure that current document doesn't get returned in the autocompleter
        $addExisting->setSearchList($this->getRelatedDocumentsForAutocompleter());

        // Restrict search fields to specific fields only
        $addExisting->setSearchFields(array('Title:PartialMatch', 'Filename:PartialMatch'));
        $addExisting->setResultsFormat('$Filename');

        $this->extend('updateRelatedDocumentsGridField', $gridField);
        return $gridField;
    }