You got my attention for sure! I put a 6.7 in a 72 Demon recently so I feel your pain already! Hah! I did a long winded thread on my build here on FABO. I ran into a multitude of issues but none that were insurmountable. It is now hands down my favorite car to drive! And I have one nasty Cuda so that should tell you how much fun it will be to drive. I got zero regrets, but I sure made a lot of mistakes along the way. There are several modern swap threads on FABO I would sure read them all as it will save you a ton of work and cash. There are some super creative guys on here for sure. I am just a knuckle dragging racer so mine got built that way, some of these guys have simply just built beautiful cars.