some came with 6.5's some came with 5.25's. some came with i dunno what size in the dash, and i dont have a clue what size is in the rear. i'd like to change mine, but i dont want to change them til i'm ready to do the wiring for the x-over and tweets, cause that panel looks to be a real pain in the a$$ to get off.
umm the drum looking thing is the spacer for your speaker. take your door panal off and roll down your window, its like 1/2 inch between metal and steel. oh on the 5 1/4 thing just make or buy a reducer.