Follow the lower radiator hose from the radiator to the back of the engine. Where it connects to the engine, you will see wires plugged in to the sensor
No the engine is not interchangeable.
Yes, but it is a federal offense to put an older engine into a car that is newer.
The 1995 Honda Civic speed sensor is located on the front passenger wheel. The speed sensor will be found on the inside of the brake rotor.
Unplug it and unscrew it.
behind the timing belt covers
as long as there has been no engine swapping going on, yes
It is a sensor that screws into the exhaust pipe or manifold that senses the amountof oxygen that is in the exhaust and controlls the amount of fuel it feeds the engine.