If it’s not the main seal, like above, it could be the
rear galley plugs (1/2” Rachet square head to remove) and riffraff sells the o-ring or plugs plus o-ring
Rear cover. To reseal, this must come off with the rms <img src="https://www.powerstroke.org/forum/images/smilies/frown.gif" border="0" alt="" title="Frown" class="inlineimg" />
Hpop line leaking (engine is tiled back and will run back to towards the rear)
Cracked cylinder wall (really, anywhere)
Those are the only things I can think behind there.
~Don’t overthink something simple~
...:uptight people suck:...