66 dart: engine swap or turbo /6?

So I picked up a 66 Dart 270 a few weeks ago with a 225 /6 and I have a 318 I was going to put in it. Looking under the hood now I'm starting to wonder if it'd be worth it to use the 318 because it looks like I'd have to move too much around. I'd still like to get some performance out of the car either way so I'm also considering turbos for the 6. Any one have some experience or input on this?