How can I engineer, design (select) & install (set-up) the perfect car audio system?

Monday, October 4th, 2010 at 3:00 pm

I would like to know how can I engineer, design (select) & install (set-up) the perfect car audio system?
Like an easy calculation or formula or table (matrix) in order to determine the best (required) head unit, amplifier, speakers type & sub-woofer based on the car or van type.
I looking for just a "Rule of thumb", a starting point, a reference point!
Rule of thumb