The engines with the full flow oiling capability started in 1959, I believe. There will be two large oil ports (1/2" NPT) on the driver's side of the engine, and a round dowel pin close to the forward one which needs to be pushed in about 1/2" to reroute the oil flow. There's lots of discussion about whether or not it's a good idea to do that.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!