I am looking into a electric fan and I was wandering what is the minimum CFM I should look for? I want to make sure that whatever I get is big enough. ALso I want to try to mount it and then put my stock fan shroud back on so that way the botttles will still have somewhere to mount to. I am looking at the flex a lite fans. I want something that is a kit and come with a thermostat and everything and I also want to be able to shut it up whenver I need to.