The oil pressure sensor, oil cooler or one of the lines

missing oil gallery plug

A picture is worth a 1000 words.

Follow the leaking oil to the leak?

I can’t tell hence the question smart ass

As I mention many times up here --- ENGINE SERIAL number is needed. There is a service bulletin about oil leaking and oil line replacement in which could be the issue. It possible can be a good idea to take your boat into a oem dealer and have it looked over and see if the service bulletin is in fact per your engine and the issue at hand.

IMO in a lot cases with stock oem apps it might be a better avenue for one to seek out an OEM dealer instead of guess work to have all looked at and possible any outstanding recalls and service bulletins that possible can be attached to your engine and outdrive .

You can put some dye in the oil and look at the engine under a black light (iPhone LED flashlight works too). Much easier than guessing where it's coming from. NAPA has it.