Tips on Customizing GS Testimonial Slider

How to Hide GS Testimonial Lite Admin Menus

function plt_hide_gs_testimonial_menus() {
	//Hide "GS Testimonials".
	remove_menu_page('edit.php?post_type=gs_testimonial');
	//Hide "GS Testimonials → All Testimonials".
	remove_submenu_page('edit.php?post_type=gs_testimonial', 'edit.php?post_type=gs_testimonial');
	//Hide "GS Testimonials → Add New".
	remove_submenu_page('edit.php?post_type=gs_testimonial', 'post-new.php?post_type=gs_testimonial');
	//Hide "GS Testimonials → Settings".
	remove_submenu_page('edit.php?post_type=gs_testimonial', 'testimonial-settings');
	//Hide "GS Testimonials → Pro Plugins".
	remove_submenu_page('edit.php?post_type=gs_testimonial', 'gs-add-ons');
	//Hide "GS Testimonials → Free Plugins".
	remove_submenu_page('edit.php?post_type=gs_testimonial', 'gs-plugins-free');
	//Hide "GS Testimonials → Help".
	remove_submenu_page('edit.php?post_type=gs_testimonial', 'gs-testimonial-help');
}

add_action('admin_menu', 'plt_hide_gs_testimonial_menus', 11);

Where do I put this code?

How to Hide GS Testimonial Lite Meta Boxes

function plt_hide_gs_testimonial_metaboxes() {
	$screen = get_current_screen();
	if ( !$screen ) {
		return;
	}

	//Hide the "Testimonial Author Image" meta box.
	remove_meta_box('postimagediv', $screen->id, 'side');
	//Hide the "Testimonial Author Details" meta box.
	remove_meta_box('gs_testimonial_sectionid', $screen->id, 'advanced');
	//Hide the "GS Testimonial Slider - PRO" meta box.
	remove_meta_box('gs_testimonial_sectionid_pro', $screen->id, 'advanced');
	//Hide the "Other Info" meta box.
	remove_meta_box('gs_testimonial_sectionid_pro_sidebar', $screen->id, 'side');
}

add_action('add_meta_boxes', 'plt_hide_gs_testimonial_metaboxes', 20);