MARINER : 20C (THRU PROP. EXHAUST) Model Serial Ranges 6A9-000101 THRU 010111 6A9-010112 & Up 6A9-250101 THRU 250819 6A9-250820 & Up 6A9-300101 THRU 306542 6A9-306543 & Up 6A9-550101 THRU 550693 6A9-550694 & Up