Kurt,
I figured that the build date was too late, however, the vin stamped numbers do match a (later) style of Saginaw vin stamp (some later Super T10's have the same characters as well). I was scratching my head and figured I would post it up here anyway. The shifter is a 70 plus unit, however, anyone could have bolted that on. Please remove this lost and found if you think it is necessary.