If your truck is carbureted, then the fuel filter inside of the carburetor where the fuel line connect to the carburetor. Remove the fuel line from the carb. Then unscrew the large nut on the carburetor that the fuel line screwed into. The filter is in there. Bu
y the new filter before removing the old one because you can't drive it once the line is disconnected.
**** Use a rag to catch gasoline as it will flow out of the fuel line once you unscrew it. (Only a couple of ounces will flow out).