I need some help! I have a 1960 JD 440IC Serial #456945. I had to replace the bull gear in the final drive. I am putting the track back together. I order a master track pin JD part # M2952T. I put the new pin in, but it is too short. The pin that came out was a straight pin, all the links on both tracks are the same. There is no master pin. I am at least the 4th owner and the pin that I drove out was determined to be the master pin due to the fact the final drive was cracked and welded, 2 track shoes had different bolts and the straight pin was about 1/8" shorter. The M2952T pin is 1/2" too short, the pin length from the head to the end of the pin is 5 3/8".The pin is just flush with the end of the link. Does JD or someone else have a 1/2 longer master pin, or can I use a Grade 8, 1.0" bolt with an 5 1/2" shoulder?