WooCommerce Custom Ecommerce Tracking - almost there ...

Using an excellent resource cited below and helpful comments I've build out a Wordpress plugin (as per code) to send WooCommerce transaction data to a custom CRM. From the thank you page.

I've got stuck however. I can send the transaction value, tax and shipping details but I can't seem to call, or send; a) Product Name b) Product Category c) Product ID d) Details of product splits between more than one product

Any thoughts, links or advice much appreciated. New to this and trying to battle through.

<?php
/**
* Plugin Name: eCommerce Tracking
* Plugin URI: 
* Description: Send shopping data to CRM
* Version: 1.0
* Author: fly
* Author URI: 
* License: GPL2
*/

add_action( 'woocommerce_thankyou', 'my_custom_tracking' );
function my_custom_tracking( $order_id ) {



// Lets grab the order
$order = new WC_Order( $order_id );

// Order ID
$order_id = $order->get_order_number();

// Order total
$order_total = $order->get_total();

// Order e-mail
$order_email = $order->billing_email;

// Order Billing First Name
$order_fname = $order->billing_first_name;

// Order Billing Last Name
$order_lname = $order->billing_last_name;

// Order Billing Address 1
$order_bill1 = $order->billing_address_1;

// Order Billing Address 2
$order_bill2 = $order->billing_address_2;

// Billing City
$order_billcity = $order->billing_city;

// Billing State
$order_billstate = $order->billing_state;

// Billing Postcode
$order_billpostcode = $order->billing_postcode;

// Billing Country
$order_billcountry = $order->billing_country;

// Billing Phone
$order_billphone = $order->billing_phone;

// Order Tax Cost
$order_tax = $order->order_tax;

// Order Shipping Cost
$order_shippingcost = $order->order_shipping;

// Order Currency
$order_currency = $order->order_currency;

// Product Category
$order_category = $order->term_id;

// Product Name
$order_product = $order->item_id;

// Product Quantity
$order_quantity = $order->quantity;

// Product SKU
$order_sku = $order->sku;

// Product Price
$order_price = $order->price;


?>



<!-- Start Tracking code -->
<script type="text/javascript">
var _ss = _ss || [];
_ss.push(['_setDomain', 'xxxxxxxx']);
_ss.push(['_setAccount', 'xxxxxxx']);
_ss.push(['_trackPageView']);
(function() {
var ss = document.createElement('script');
ss.type = 'text/javascript'; ss.async = true;

ss.src = ('https:' == document.location.protocol ? 'https://' :     
'http://') + 'koi-3Q40EJNC5K.marketingautomation.services/client/ss.js?  
ver=1.1.1';
var scr = document.getElementsByTagName('script')[0];
scr.parentNode.insertBefore(ss, scr);
})();
</script>



<script type='text/javascript'>

_ss.push(['_setTransaction', {
    'transactionID': '<?php echo $order_id; ?>',
    'storeName': 'Reco Surfaces',
    'total': '<?php echo $order_total; ?>',
    'tax': '<?php echo $order_tax; ?>',
    'shipping': '<?php echo $order_shippingcost; ?>',
    'city': '<?php echo $order_billcity; ?>',
    'state': '<?php echo $order_billstate; ?>',
    'zipcode': '<?php echo $order_billpostcode; ?>',
    'country': 'UK',
    'firstName' : '<?php echo $order_fname; ?>', 
    'lastName' : '<?php echo $order_lname; ?>', 
    'emailAddress' : '<?php echo $order_email ?>' 
}, function() {

    _ss.push(['_addTransactionItem', {
        'transactionID': '<?php echo $order_id; ?>',
        'itemCode': '<?php echo $order_sku; ?>',
        'productName': '<?php echo $order_product; ?>',
        'category': '<?php echo $order_category; ?>',
        'price': '<?php echo $order_price; ?>',
        'quantity': '<?php echo $order_quantity; ?>'
    }]);

    _ss.push(['_completeTransaction', {
        'transactionID': '<?php echo $order_id; ?>'
    }]);

}]);

</script>


 <!-- End Tracking code -->
 <?php
 }

via Chebli Mohamed