[kpriest]

Actually, skin1/main/order_invoice_print.tpl references skin1/mail/order_invoice.tpl - that's the one you need to edit. (x-cart gets pretty unnecessarily convoluted sometimes!) Remove the following:

{$lng.lbl_billing_address}:
----------------
  {$lng.lbl_address}:    {$order.b_address}
  {$lng.lbl_city}:       {$order.b_city}
  {$lng.lbl_state}:      {$order.b_statename}
  {$lng.lbl_country}:    {$order.b_countryname}
  {$lng.lbl_zip_code}:   {$order.b_zipcode}