95 Pantera II, 3 pics, 3 questions!

1. The hole is in fact another seat post placement. Your boat may have a small sign that reads “remove front seat when running”. That is to put the seat down so it doesnt pop loose on deck. Also, another fisherman can sit down lower in the boat and use a seat(my dad did that). Your deck extension has a larger hole to allow the entire post to sit down into the pin base. That being said, it looks like someone put a black pin bushing in there, which it should not have.2. Not sure on the mount but would think it should not lift freely.3. The ports were if you wanted to use accessories…….spot light, night light, etc. You can get a 3 prong trolling motor plug and splice a fitting like the “cigarette lighter” style receptacle. Some spot lights still have the 12v accessory type plugs found on cars. or you could charge phones, etc if necessary.4. Perko key would need to see if the factory still has any. Or you might have to contact Perko company.Good luck!96 Eyra/12 Mercury 175 Pro XS with 2015 single axle trailer2017 Victory Gunner

Normally there is no plastic bushing on that center location. Should just be metal/brass base. As far as 3 wire Im not electric smart but I assume a positive / negative / ground wiring…96 Eyra/12 Mercury 175 Pro XS with 2015 single axle trailer2017 Victory Gunner

Not a knowledgeable “Bird” guy, but I very much doubt that the transducer bracket is supposed to have a screw in it. It most likely is supposed to “snap” down in place so it can kick up on impact with something instead of breaking off.