The fuel filter on a 1986 Chevy Celebrity is located
on the frame rail, near the fuel tank, usually on the passenger side. However, the exact location can vary slightly depending on the engine and specific trim level. You'll likely need to look closely along the frame rail near the fuel tank on the passenger side to find it. It's often a cylindrical canister.
It's recommended to consult a repair manual specific to your 1986 Chevy Celebrity for the most accurate location. A Haynes or Chilton manual will have diagrams and detailed instructions.