The normal setup is for the line at the middle of the canister to attach to the same port as the oil pressure line, near the exhaust pipe about 4 inches up from the oil pan rail. This forces the oil through the filter element from the outside. The oil gets filtered either way, but the line routing is simpler if the return line exits at the bottom of the canister and goes back into the engine at the forward port almost at oil pan level.
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!