Don't worry about getting rid of all the rust...the poor 15 loves to bind with it and thats how you will get best results. Obviously you don't want big chunks but surface rust is ok...contact the folks at west coast coatings for specific instructions and follow them...they know what their talking about. I would use the chassis black top coat too... you can use it following por 15 or spray with their self etching primer up to one year later and then top coat. You can google west coast coatings and it will come right up. Good luck!
