When putting on parts if there is no very visable differance but one is marked left and one is marked right, don't most manufacturing co.'s go with driver side is left and pass. side is right as in upper ball joints on the 97 F-150?

 

Drivers side = left

Passenger side = right

 

I work in automotive manufacturing. Left and Right are always stated as "In Car" position. Meaning left and right as if you are sitting in the driver's seat.