I believe the earlier boats (and I don't know at what hull number they switched) had 2QM15s, and later boats have 2GMs. The QMs have a cast iron block, and are heavier than the GMs with an alloy block. I believe they also went to a larger prop shaft when they switched engines.
I have hull #205 with the older QM15 engine. It's fresh water cooled... which is just fine on Lake Michigan. After 20 years, I replaced the injectors just as routine maintenance. I've not had to do any other major maintenance in the 14 years I've owned the boat (knock on wood).
I don't believe the boats came with a masthead light standard. There's only a steaming/spreader light.
