Is there any easier way to drain the water on my 180se Astina? What Anti-Freeze do you guys recommend?

Unclamp the pipe at the bottom off your radiator (Closes to the Block)

unboltin that hose though may just drain whats in the rad and the header - for total drain, run the engine for a few secs (from cold) until its all come out, then you can fill up with exact amount as specified in the manual (6 liters ish)

There is a small plug at the bottom of the radiator. It sits behind the driver side's spotlight or plastic cover for the models without spots.