Someone needs to post a pic of the oil galleries on the driver's side, showing the plug that gets driven in to make the 261 a full flow system. My 261 engine is in storage where it would be difficult to get a good picture. If the plug is in the "out" position, it's a bypass setup, but if it's been driven "in" the filter ports need to be connected.
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!