I've got a 19' cuddy with a fully enclosed top. The lake is absolutely gorgeous right now, and while the days are still warm the nights are down in the 30's. I'm a total wuss when it comes to cold. What's a safe way to heat my boat so I can spend a night or two on the lake before I'm done for the year? Maybe a 12v electric blanket or some kind of small cabin heater. And there's always the toilet paper soaked in alcohol trick, but that seems like it could end badly. Right now I don't have any deep cycle batteries or any other secondary power source, but I could add something.