Rotella diesel oil in a 440 ???

What do you mean by "noise" and "growl"? The lifters he chose are anti pump ups..Thne they may be noisey when the rockers are adjusted properly. They should make a very soft ticking sound, that might be slightly louder during part throttle cruise or light throttle. If you have no background, you may want to have a local friend go over setting the valve lash with you. IMO, it probably is in need of adjustment. For anti pump ups, I'd be looking for apprx 1/4-1/3 turn past "zero lash" with them hot. The missing zinc "package" is now also available from Comp Cams in a small bottle. To be honest, it should be used every oil change, but then you can run any oil you want.