help! i dont want a ricer

I have read somewere that dart sport lights and feather duster dusters would get 30+ mpg with a overdrive 4 speed.I parted a spirit of 76 dart a few years ago that had a aluminum framed hood and intake and oter parts to lighten and I imagine some pretty tall gears. That would be a cool driver if you can find one .If not it is hard to beat a import for reliability and econimical cost to operate as much as it pains me to say it and I have owned many over the years.Now if you really want to think out of the box find yourself a vw rabbit diesal you can pick these up for cheap when they wont run any more and throw a set of rings in them and get 50mpg just be carefull like there namsake they multiply and almost becomes a obsession to buy every one you find for parts that you will probebly never need Ive had about 30 of em.Incase you wondering they are super simpile to work on and parts arent to bad I could rebuild one enough to start and run reliably for about 50.00 and 4 hrs time dont even have to pull engine.Boy this is wordy for me lol