i have a 1980 16 foot sylvan . beam 6 foot,package weight 1050 lbs ,it has ribs along the bottom of the hull ,made of rivieted allumiun, 30 degree bow rise. it has a 1987 mariner inline 4 45 hp(maybe it is 40 at the shaft ) , with a 2:1 gear ratio . it is used in fresh water and trailer when not...