Looks like an early model Quicksilver Commander 2000 since it mounts on the bulkhead, not in it and the control and electrical cables are exposed. I think I see a kill switch under the key switch and trim controls in the handle.
Mr. b, that purple or red with purple stripe is not 12v perse. Red is 12v. When you add purple the caveat is the ignition switch has to be somewhere besides off to get 12v which is what you want when you want to turn everything off when the boat is not being used.
I asked before about the "brown" wire. Is it brown shoe brown or tan? Is it part of the harness and pigtailed out or is it alongside the harness like an aftermarket add on for some specific function?
Brown/white....trim sensor? Do you mean a wire that would contain position information for engine trim if it had a sensor? That may be a companion to the brown (shoe brown???) that you referred to.
Other than the brown as mentioned above, your assessment of functionality per color is accurate. In addition there is a red with yellow stripe which is voltage from the key in the Start position to the starting solenoid coil to activate it and spin the starter. Then there is black with yellow stripe and yellow with black stripe. First one is engine kill aka ground from the key switch in the OFF position. It grounds out your triggers and kills the engine. Then there is the choke or fuel enrichment 112v for the yellow blk stripe. When you push in on the key you put 12v on that wire.
That about covers it for an 8 pin connector. Only other thing would be PTT signals which would be 12v on the blue for trim up and 12v on the green for trim down (blue sky, green grass). This signal level (just energizes the circuit not high current drive power.....like the red/yel stripe does for the starter solenoid) signal power goes to the trim relays/solenoids in the engine.
