I have attached the page from the 1963 Oldsmobile Master Parts book. All F-85 fuel tanks are the same part number. The difference is in the “bolt on” pick-up and fuel gauge sender unit. You should be able to use ANY 1963 F-85 fuel tank and use your Jetfire fuel pick-up, fuel return and gauge unit. This unit uses a fuel return (second steel line shown in my last post) coming out of the top of the tank. The fuel return system was used on all Jetfire’s and California F-85 cars, to meet the low fuel emission requirements of the day. The fuel pick-up, return and fuel gauge sender units are interchangeable with all tanks. When you swap this part, make a new gasket and seal it well. The final difference in the Jetfire fuel system is the fuel pick-up sock or filter that fits on the pick-up tube in the bottom of the tank, it is longer/larger (see attached). I am not real sure just how critical this is, they can be hard to find.