Ge nautilus unit leaking when running . how do you get to the water outlet o-ring

This is a suggestion, and not the definitive answer...

to prove where the leak is . there is some heavy lifting.
Move your dishawasher, and look underneath, or around the bottom (all around)
you will see witness signs of water runs . this should point you in the location of the fault...sometimes helps to place the washer onto some bricks - you will see easily where the root problem is for the leak.
Good luck - please feel free to come back to me.