I'm planning on ordering some alpine type r speakers for my ex sedan. Do I need anything? Crutchfield says they will not fit, but I know people that have gotten around with other speakers. They are 6.5s and really thick compared to other speakers. Is the thickness the reason they won't fit? Or should I should I just look for 5.25s for my front doors, and if I go with the 5.25s, do I need any special bracket or will the stock one be fine?