The J5 could also be power buckets, but the interior codes says bench. The codes in this book say J is from 450-489, tag is J5 so it could be 455, 465, 475 or 485. The Z8 is only buffed paint, book says for silver only. The door jamb paint doesn't look pale yellow. The 48 is stamped in from the top, usually inspection stamp, but nobody knows for sure. Does it have the rear heater? They are great in the winter. Nice looking Imperial.