Vance-----hood fenders front bumper doors are interchangeable..the only diff. in eg's are sedans fenders are 1 inch longer and bumper is just a little bit different where it meets the fender...taillights and rear bumper and not interchangeable....as far as exhaust, i have a friend here that put a stock EP3 (02-05 civic si) rear section on his hatch no problems......if u wanna test fit it, i have one from an 02 si at home.......lmk.....door panels interchangable as long as power/manual..which u prob already knew..lol