440 Oiling mods

I'm in the same boat on this one. I want to take care of this issue and avoid a broken engine. Can anyone post some photos of the simple mod where the #4 cam journal gets grooved and the oil feeds at the decks get restrictors? What is used as far as restrictors, is it pipe plugs with a small hole drilled, or can I purchase the restrictors somewhere? how deep does the groove in the cam journal need to be? Is this mod adequet enough for a 6500 RPM combo?