the stock speaker size is a 5x7/6x8. u could use an adaptor plate for the 5 1/4" speakers into the stock openings but i wouldnt try fitting 6 1/2" in there. ur best bet would be getting a 5x7/6x8 component set. mount the woofer inside the stock location and mount the tweet on the sail panel. i know JL and Infinity sell a component speaker set like that.