JBA offers a variety of products to meet the demands of the performance enthusiast. Headers, performance exhaust systems, and ignition wires are all available to ensure you have the right fit and performance desired. Headers - Cat4ward - 1-5/8 in Primary - 2-1/2 in Collector - Stainless - Natural - GM LS-Series - GM Fullsize SUV / Truck 2003-06 - Kit. Please do your own research to confirm this part fits your vehicle. Processing begins as soon as an order has been placed, therefore we cannot change, cancel or modify orders once they have been confirmed. Most e-mails are answered within 24 hours, including weekends and holidays.