71 Dart Front Disc Conversion Questions

I have a 71 Dart with slant 6 and drum brakes, I have a chance to buy a disc brake set up off another 71 Dart that includes the spindles, rotors, calipers, everything except the booster claims the seller.
I am not 100% sure what the spindles should look like is there a part number or does anyone have a picture? Should these be the Kelsey Hayes 4 piston design?. Can I re-use my old lower control arms?

Thank you in advance