I plan on replacing my 2 front speakers and 2 rear speakers in my 91 mk3, my main concern is connecting it to the stock cables do I have to worry about them being coaxial or anything like that or are they all the same? Also do I have to worry about wattage I do not plan on getting a full system with an AMP and subs I just want to replace the speakers. I was thinking about getting these http://www.amazon.com/gp/product/B000P0PF9G/ but not sure if it will fit since it is coaxial.