Duane can only do 70-72 sheets. He had no ideas unfortunately. He told me those are all manufacturer codes which are different from UPC or Fisher Body Codes. Without a key, there is no way to figure it out. When Duane did the 70-72 A bodies, it took him 18 years of cross referencing build sheets to finally get the last code. That is what he had to do to figure everything out. It's a shame. That POBF is in beautiful shape. You are lucky to have found it.