I have a Jewelled fuel cap but i don't know how to remove the existing plastic lanyard holding the old cap on. Anyone had any experience of removal of the plastic lanyard before i start heaving on it, and possibly causing some damage to the flap hinge etc?

 

It just pops out. Pull on it close to where it attaches to the lid. You can use a plastic trim removal tool.

 

Have you seen any mileage improvements with the jewelled cap ?