A few years ago, I was able to go all thru the old Huron LIghtship in
Port Huron, MI. I was surprised to see that it had 2 old 671 GM
Graymarine diesel engines driving one prop thru a common gear box. The
ship still had to be towed from its dock on the St. Clair River to its
location about 5 miles north in Lake Huron because of the current at the
mouth of the river.