I do have a fuse panel under the bow of the boat. Just haven't gotten that far on drawing up the dash diagram yet.
However I do not run a main disconnect, nor do I currently have a main breaker or fuse yet. I also need to fuse the MSD box. MSD claims you don't need to, but I honestly don't see the harm in putting a 10 amp fuse inline with it (since it'll only draw about 5.5 amps in my boat anyway).