i have a 95 cougar

how do i go and install a cd player to replace a factory radio???? and how do i change the 6by9s and tweeters???

the car should have a DIN opening for the stereo. you remove the fctory stereo, get a wiring harness specific for your car, wire it up then install the stereo and harness. The new stereo will have a mounting sleeve, you slide it into the opening then lock it down. Then slide the stereo into the sleeve (be sure to attach all the wiring first).