I am going to replace the door and rear deck speakers in my 2001 Mustang without the Mach. I don't know a whole lot about speaker specs so I could use some advice on what size, watts, ohms, 2,3,4-way, etc. I already have subwoofer system installed so they don't have to be the best, just want something that will sound good along with it because my factory voice coils are blown. I'd prefer not to have to run another amp, but that isnt too much of a problem if I need to.

 

If you arent going to go with another amp then I would suggest something simple as 5x7 replacements. Most reputible brands make that size and then its more or less a plug and play setup. Because you have a sub, a 2 way speaker is probably fine in all corners.

What I am doing is Getting 5x7 components ( you can adapt 5 1/4 or 6 1/2 if you want) for the front, and 5x7 2 ways in the back that both support the same RMS and getting a 4 channel Amp to drive them. This will work with My mono block amp and 2 12s in the trunk. Obviously this ups the cost a bit and requires extra wiring but it will allow for better volume with less distortion where as deck to speakers increases the chance of distortion. Are you still running a factory Deck? If so, and cost is a factor, I would suggest a new Deck along with the drop in replacements.