We don’t fully understand your question zookae?
The boat is rated within tolerances on some and they will provide a rating plate to accommodate the older Jaguar models that has 245 plates, they will not revise the 280-285 plate models.
They did not want the larger platforms on the boats back then and there were a variety, including a V6 Mercury 300 that weighed about 850 pounds at one time. OMC had a big 3.x liter block that was also a big V8 or V6 that was a massive platform at that time. Those are no longer a factor as engines have shrunk in relation to ponies.
BCB