[msmith10]

Adding to Al and Neil's posts:
No idea what your boat is like or your capabilities but:
If you don't understand basic AC wiring, buy a copy of Richter ($15 at Lowes or HD). It is not about marine wiring- it's for residential/commercial wiring but it's the simplest and most useful book to learn the basics and you can learn the variations needed for a boat after that. Nigel Calder book "Boatowners Mechanical and Electrical Manual" will answer a lot of questions about everything and should be on every boat.
It's very possible your AC wiring is solid copper. Even if it's not, easiest and safest to rip it all out and start over. Then you'll know and trust your system. Use only braided/tinned marine cable. No wire nuts should ever go on the boat anywhere. Get a set of ratcheting crimpers- you'll use them a lot. A good set is $125 but a passable set is $25 on Amazon. Use adhesive lined heat shrink connectors.
Add a GFCI after the main breaker then branch that to your outlets as Dan said.
You can get a very cheap (< $10) reverse polarity indicator at almost any hardware store- I got a plug in unit sold as an outlet tester. I leave it plugged into an outlet in the cabin and check it as soon as I've connected to shore power. It shows a set of idiot lights that indicate if the incoming circuit was wired correctly.
Renewing the wiring on your boat isn't showy but it will really be one of the most satisfying jobs you'll do. And it's much more pleasant than replacing the head.