If you are in the south and you hit a cold spell, just drain the block and manifolds. If the boat is going to sit more than a couple of weeks, then I would winterize it. I take my time to make sure everything is done properly. It takes me an hour or two. I follow the factory procedure to the letter. After changing the oil I back the boat back into the water and let it idle for 10 minutes to get the new oil and stabilized fuel into the engine. When I get it back to the house I drain the block, and fill it with antifreeze and fog the engine at the same time. Once that is done I take the tension out of the belts, remove the impeller from the water pump and store it in a vacuum sealed bag or jar of antifreeze. I reassemble the pump and reinstall it on the engine. I remove the battery from the boat and put it on the charger once a month while in storage. That is what I do for a 5-6 month winter storage. Sometimes in the early and late season in PA it sometimes gets cold so as a precaution I will drain the manifolds and the block especially if I know the boat is going to sit unused for the week. The garage I store it in stays in the 40's most of the time during the middle of winter, but I use the antifreeze for corrosion protection as well as burst protection. In the spring when I put it back in I put everything back together, and let the boat idle for 10 minutes to flush the old fuel out, and make sure everything is working properly before going out on a cold lake.