Every one seems to be in to little things like paint over spray. I wrote about this in 1991 and I think some one re-wrote my Article in the drive-line. I wrote it just to see if people were interested in which shift their part was made. Every one seems to wont to know what all the markings are for. Not mentioned here, is that you also have the markings G.M 1 or G.M16 or what ever in many cast iron part. This is because the casting mould ( which were many) were marked 1,4,36 or what ever,so that if a problem arises with a part the supplier knew which mould to repair or destroy.