I know there was a thread on identifying gearboxes by the factory number on the box, but I can't find it. I am looking for a SI box for an 89 and the local boneyard has several. He konows that they will fit, but cannot tell me if the are 88-89 or 90-91 which I know have different input shafts. Can anyone help??? Thanks (Fault in old box, cracked shift forks)