I would think you would want all circuits protected by fuses. My '77 has fuses for everything. I know I have pics of the fuseblock but can't find them. When I find them, I will post them.
I do have another wiring diagram though I don't know what years this covers. Essentially the same thing you already have.
Are you a facebook guy? The Mastercraft Project there is specifically for '68 - '85 boats with some guys that are really sharp regarding '76 and older boats.
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