Just to explain why I listed it as J code ,302 4V . My Ford spec book lists as Mustang/Cougar w/302 2V-4V. This book does not list any Shelby specs by themselves. I realize there are many different books by many sources and info may differ. So,that being said,I believe this tag is correct for Mustang and Cougar with 302 2V-4V. If not correct for your GT 350 ,please use whatever source of info you trust.
Thanks