Back in the day, before the products we now have were available, dealers (and boat owners) used to put in shore power systems with home type Square D breaker boxes, which are no longer up to code anymore. They also used solid core wiring found in home electrical systems, which also are not code anymore. You need to use a marine breaker panel with stranded wire (3 conductor - white, black and green). Sorry if I am telling you stuff you already know. You need to have a panel that has at the very minimum a double breaker for the shore power coming into your boat. By double breaker, I mean it breaks both the positive and negative sides, if there is an overload. If you have other loads (like a battery charger) hard wired into the system, then you need a breaker for each load. Each breaker, whether it be a main breaker (double) or single, will have switches on them so that you can switch off the device at will. So, depending on how many items that run off of your shore power depends on how big your panel should be to accommodate all of the breakers for each device (load). Blue Seas makes such panels. The panel itself should be installed in a place where you can easily access it just like your 12v electrical panel is. Perhaps there is space next to it where you can cut a hole to accept the size AC panel that you choose. If not, then perhaps another location and if not, then maybe you or someone for you can build a box/cabinet to house the new panel. Whatever you do, if it can possibly be touched by someone on the back side of the panel, then you need to protect it with a backing box so no one accidentally electrocutes themselves accidentally. Breaker sizes (like 5A to 30A, for example) match the load device you are using. If you have outlets to plug in AC products, you need to have GFCI outlets near water sources like the galley or head to be up to code. This should get your started.
