Headphones indicate there must be (or may have been at one time) a DVD/Monitor installed in the vehicle. Does it have a flip down screen on the ceiling or in the back of the headrests?
Audiovox is a brand name notorious for making all kinds of automotive electronics and most popularly DVD...
That will depend greatly on what type of amplifier you will be running the components on. Without knowing what amp configuration you are planning to run it is impossible to suggest what type of components you should use. Speakers and amplifiers should be chosen together to match the system up...
Voltage is not the issue amperage is. 12 volts is 12 volts period. An amplifier draws a lot of amperage (current) not voltage. If you are going to be running a 500W-700W or less amp then you will be fine. If you run more than 700W amp then you will want to upgrade your alternator not your...
The only stereo systems I have ever seen that are rated for 2 ohm loads are the stock Jeep/Chrysler Infinity amplified systems and the GM/Bose aplified systems. Other than those 2 systems all stereos are designed for 4 ohm loads. If you are replacing a stock 2 ohm sub with an aftermarket sub...