Need advice: 318 or 340 for a 68 Dart?

I'd stick with the slant if this were ever the case.

Old cars, hot motors, and people who don't understand them is a recipe for trouble.

The Dart's 6 cyl was removed by someone, it has no motor currently. And yes if this car was going straight to my daughter I would put a /6 back in. But I plan on enjoying it for a while first. And if you're wondering why I would ask a seemingly obvious question it's because I'm a girl so I have limited experience in that department. I can change the oil and do my own brakes but I'll leave everything else to the guys. So thanks for the help, my husband's not a car nut so he can't help.