| Re: 94 DX Hatchback Rear Speakers
A buddy of mine had a couple of hatchback civics ('89 and '91) and in both we just bought aftermarket 6x9s and pre-fab boxes for each. In one he mounted them on top of the sub box, it was big enough that the top was level with the seats, so the 6x9s fired nicely into the front seats.
In the other we mounted them to the roof, and that worked well you just have to keep them out of the way of the mirror.
Wiring just runs along the floor panels and behind the trim like any sub wiring would. He had an aftermarket deck. Without one of those, you can just splice into the factory wiring. I don't know if the factory deck has wires for rear speakers if the car only has fronts, but you could always split the fronts if need-be.
If you want something more complex or stealthy than that, I'm not able to help you there. | 
