thats not the whole serial number
it will begin with letters like AT example: AT81F-xxxxxx
the prefixes began like AT81F or AT90, AT83F, AT34, AT35, AT36, AT13F
If the dataplate is unreadable then look on RH side along where the hood runs on the frame, it might be stamped there or check the right front fender.
usually there are a couple locations for the dataplate, on top of the dash or on the front of the firewall on the front of the truck or possibly the kick panel behind your feet.