Depends on how much you want to spend. If you are on a budget, you can get Pioneer / Infinity / JL Audio 3-way speakers for relatively cheap and they will sound great. If you have money to drop ... I would invest in a component 6.5" system for both the front and the rear ... they have brackets that will convert a 6 x 9 opening into a 6.5" opening and a spot for a 1 1/4" tweeter to go into.