Every thing you have given us points to a 1962 air force tug.
It has a hyd clutch rather than a standard clutch.
rear axle code E 32 was built on May 3 1962
Radiator 662 was built in June 1962
Serial # 171127 was assembled in July of 1962.Does it have the trans cooler up by the radiator????? ? The grill should not be egg crate kind because that is for the larger 801's. The grill with the round cyclops medallian as you call it was used until July 1962 when the last of the 600's were built. In Aug 1962 it was changed to the newer grill and had thousand series model #'s. The thing that has been stumping me is what I think you are using as your model #. 621162. A 621 is a 601 tractor; 4 speed with no Pto or hyd system. The 162 has to have some thing to do with the fact that it is a tug but I really do not know. Most tugs I have heard of were 821's and they are rare. A 621 tug is even rarer and I have never even heard of one. If this turns out to really be a 621 Air force tug; please keep it orginal or at least as much as you can. Maybe Tony Jacobs will chime in on this because he knows a lot more about these tugs than I do. You may even try sending him a e mail. Can you post a picture of it????? ???
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