I added a picture of my mango Tarpon 140 cockpit and tankwell to the Photos. It's basically standard stuff, but we all do something a little different.
When I bought the Humminbird 525, Scotty didn't make a mount big enough for it so I crafted a mount out of mahogany to replace the Scotty mount I had already installed on the console. I removed the Scotty and made the new mount's screw holes match the Scotty holes. The wires feed up through the mount under the Humminbird. The wires are encased in a rubber stopper that plugs the center hole in my wood mount. It seems tight enough. I then added a circle flush mount forward to hold my triple. One problem is that the triple won't swing and lock in with the fishfinder on or off so I had to lock in the post then mount the triple to the post with the bolts. No big deal. Just an engineering oversite. I use one side for rods and I mounted my GPS to the other side. I use the center slot to store the the rod holder that I am not using. Notice too that I have a crossed bungee over the front hatch. It's a little insurance against not getting the cover on tight and a place to strap down a drybag when I need it.
In the tankwell I use a legal size basket because I like the waterproof Plano boxes for saltwater. It also holds my softsided tacklebox for freshwater. The rod leashes were fashioned from a cell phone car charger. The basket has a Scotty mount on the back for my 360 light. The rod holders are held on with cable ties. There are j hooks that lock it into the tankwell. The standard flush mounts are great to hold the anchor on one side. I mounted a V cleat for the anchor line, but I am considering adding two standard cleats fore and aft since the V cleat doesn't grab the line as easy as I would like.
Tom