How far should i go with swapping stuff out in the front end?
Yes. Just find a 73 and up A body with
factory disc brakes. Get all of the brake parts from the brake pedal out, all of the lines and proportioning valve, upper and lower control arms, and spindle assemblies complete with all the disc brake parts. When you go to buy new bushings and ball joints, buy them for whatever car you took all those parts off of. It will all work in your Dart. Unless the car you rob everything from is a power brake car and you want to retain the power brakes, buy a master cylinder for a manual brake car.