Don't know of them stamped any where on 68. on your data plate you will have a von # not your vin, this von # is stamped on the inside of your radiator suppt, usually between rad and supt, in otherwords look between your radiator and radiator supt and you should see these von #s stamped there, also on drivers side trunk rail under rubber trunk seal your von # should be there.. Your build sheet should have this # on it also. (Vehicle Order #). I have two 68 coronet rts and have been all over them, with no Vin #s stamped anywhere on body.. only vin is on dash Vin. 69 this all changed..