318 automatic, 3 speed, slant six, your perfect choice for a daily driver

I suggest you read this thread:
http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=3944014&page=0&fpart=1&vc=1

Follow it carefully. It would probably be one of your better bets to build something like this. It would likely run pretty well in addition to the fuel mileage.

Now, my perfect daily driver would be a modern car. Call me crazy, but I love the absolutely amazing driveability of a sequentially injected modern car.