1970 DUSTER FUEL TANK

There is the difference in the tanks. The trunk floor is different in 68 -69 than 70 to 76. If you use a 68 - 69 tank in a 70 and up it goes in so hard it buckles the trunk for seal and put pressure against your quarter panel. See the different location in the filler tube hole in the tanks.
here is a picture for you

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