[Dennis D 1929]

Hello all. I am a new member and eager to get answers to my many questions. I am in the process of acquiring my first model A, a 1929 Coupe. It only took me 68 years but I finally got the car of my dreams. I have no knowledge of Model A's what so ever, so please bear with me. I read on a blog some where about a fellow who said his radiator has only water in it. Thought that was strange, why would you not put antifreeze in ? I live in Michigan and would think antifreeze would be a must. Is there some advantage to only water ? Second question, my top is really in bad shape so I thought of taking it off and making a Roadster out of the car. Are Roadsters and Coupes the same length ? Thought I read some where that the coupe was longer. I know the doors are different but what other problems would I encounter ? Also what is the best Model A magazine to subscribe to. Thanks to all !