8-3/4 Noise After Rebuild..What's Normal??

When you guys state "friction modifier", are you talking about the whale oil additive?.............and should I add it now, or drive the thing for a break-in, then drain and add or change the oil..........and what about the royal purple for the oil after some miles............I've heard this oil is the best from a lot of pro's..........BUT, need input from you guys...........:book: