I am using the same motor plate in my 71 Demon 440. Would be interested in seeing pictures of your engine compartment when engine is installed. I am using TTI headers, flex fan, rack & pinion, fuel cell, and a trunk mounted battery. Good luck with your Dart.
I also will move my battery to the trunk, and will use TTI headers and a fuel cell, but will use Electric fan aluminum radiator and manual steering box.