I have a 86 300sdl with the stock speakers in the back which are either 5 1/4 or 6" im not sure but i am looking into getting 2 6X9's installed in there and i was wondering how much work that would invlove to do so without making it visible that i did so. Do you think i should have this done by a professional or do you guys think that this is a do it yourself job?, thanks Bob