When it comes to using the Trick Flows on a Magnum engine, the rocker arms that I mentioned will provide proper oiling. I confirmed this with Mike at B3 Racing, and I believe Brian at IMM also stated it. Just for further reference, a set of PRW 1.6 shaft rockers with Mikes correction kit is $590. The only reason I know is I just bought them, and a set of TF heads from him yesterday. A setup of PRWs without Mike's kit can be had for around $450. Now, like you said, time to break out a calculator!!!