Billet Aluminum Bottom Sump w/Integrated ReturnG&R Diesel Billet Aluminum Bottom Sump with Integrated Fuel Return System. This system completely eliminates the need to run the return of your aftermarket fuel pump to the top of the tank or cut into the fuel filler neck, therefore cutting install time tremendously. This sump also features "clamp in o ring style seal" instead of the competitions " ring of bolts ". To install this sump, you simply drill 1 hole into your tank ( hole saw included ),