I wish to display the total weight of all products in a customers order in the /admin/orders.php and /admin/invoice.php files so it will make shipping out an order quicker to eliminate looking up each products weight individually to get the total weight for shipping forms. I know this involves some sql queries and code additions but not sure of the exact code to create to do this.

I would like to display the total order weight below the bold order total lines in both of these pages.