I would run just one yellow top for a winch and a stereo,but for a large amp I would put one next to the amp also and make sure the engine is running with the amp turned up, the stock alt on my 16 valve checks out at 69 amps. the thing you have to watch out for is letting the battery get low, the computers in the f.i. rigs do not like low voltage, they can catch fire and burn up the whole rig, even if you only damage the ecm your still out a few bucks, optima reds are good but if you return one just don't tell them you ran a winch with it.