I once worked for diesel care and performance. They take in cores clean them up and sell them as reman they get rich of this.
they take in injector cores run them on a stand and if they pass they sell them as reman or even new. they have been sued many times and in court many times. extremely dishonest they believe that as long as they sell on the internet then the only contact with the buyer will be by phone.
I could not stand the dishonesty so i quit as have many people. they have been forced out of 3 towns due to all the problems they cause