New

I'm new to Mopar. I've been Chevy for years but I now own a 1973 Plymouth Duster (the VIN says its a 74, the title says 73). I'm excited to work on this car but it appears that it has been modified in several ways so I will need all the help I can get. First question...I'm replacing the upper control arms and found a set that will work if the front disc brakes are off of a B or E body. Will they work if the brakes are factory and how can I tell the difference?