Help choosing a v8 for my dart
The 70 would be more plug and play.
Might want to swap out the front cover to 68 and older and cast iron water pump. Gains a bit of room between rad and water pump.
Stick with a stock fit copper brass HD or AC radiator, thinner than aftermarket aluminum radiators.
Stock fixed 7 blade fan, no clutch, again for space.
The more you make it like the factory did the less trouble you will have making everything fit.
Just my 2 cents.