1970 dart swinger Wheels needed after wilwood brake front and rear

Next thing you'll find the torsion bars in the way of something and you want coilovers. Next is the steeringbox and you want a limited rack&pinion instead.
Then you can't get the leafsprings to work and you want coilovers too...

I'm no Mopar purist myself, but IMhO, since you don't seem to want to bother with anything Mopar-related in your drivetrain or setup, I think in your case you would way be better off to find a small chevy like a Nova orsomething right from the start and start with that.