on the power side of things you'll have:
2 brown earths
thin red permanent live
yellow switched ignition live
grey one for the lights one
and another one (possibly blue depending on it's age) for the remote output
the speakers will be a plug of 8 but depending on how old the car is you will have them ending in them little odd shaped plugs that go into either the amp below the stereo via a 5 pin din lead or to the joystick balance/fader controls
you really will need to junk all this and wire from new if this is the case