Woocommerce API order id (class-wc-order.php)

I needed to add some params to the order_data array in(v2/class-wc-api-order.php) woocommere and i've created a plugin so my changes wouldn't be overwritten by every update but i cant manage to get the id from the class?

I want $id to be the same the id i send in with my API

$id = 
$order = wc_get_order( $id );   

$olddata = array(
                    'first_name' => $order->shipping_first_name,
                    'last_name'  => $order->shipping_last_name,
                    'company'    => $order->shipping_company,
                    'address_1'  => $order->shipping_address_1,
                    'address_2'  => $order->shipping_address_2,
                    'city'       => $order->shipping_city,
                    'state'      => $order->shipping_state,
                    'postcode'   => $order->shipping_postcode,
                    'country'    => $order->shipping_country,
              );

via Chebli Mohamed