In 1999 This Letter of Reference was written for my work as Lead Design Checker and Shop Liaison on the Gulfstream Completion Center Automated Parts List Program. I checked well over 200 drawing packages for Product Definition, Product Structure and correct Bill Of Material. This was performed to provide Lean Manufacturing Material Usage and a Lean Storage of Material reducing overhead costs on selected GIV and GV Aircraft for the Revised Integrated Resource Management System (IRMS).