It is the routing of the wires to their different components. To get one that is for your car then you will need to purchase a Haynes Manual.
Chevrolet Impala
The 1978 two-door Chevrolet Impala model was a popular, but somewhat rare vehicle. 33,990 two-door models were produced, out of 290,744 total Impalas produced in 1978.
Diagrams should be used as guides when making changes to a car. The wiring diagram for the 1978 Chevrolet Corvette can be found in its maintenance and repair manuals.
You can find a 1978 Caprice classic radio wiring diagram at most Chevrolet dealerships. You can also find the radio wiring diagram in Chevrolet service manuals.
A 30 amp fuse is required.
It requires a 30 amp fuse.jd
A wiring diagram for this car can be found in this cars manuals. The manuals are bought at an auto part store.
The 8th digit of the Vehicle Identification Number is the engine size. Call a parts house and they will tell you.
You need to purchase a Haynes Manual and the required tools. Whay I am Saying is that it will be cheaper to have a repair shop do the job.
It is usually in the carburetor. Take the fuel line off and unscrew the fitting. It should be sitting in the housing with a spring behind it.
classic usually has more options and more chrome trim
1978 Chevrolet Big10 pickup