I've been battling an oil leak and even took it to a shop having a hard time finding source.

Ruled out rear main, turbo return. Turbo.

I'm suspecting Cam Position sensor. I took off the cover and saw abit of oil in there. not much (few drops) but there is a weep hole at the bottom of the cover to allow oil out. I back together. Cleaned motor and checked again.
There is a mounting plate for the engine mount under the sensor housing and it looked like oil on it and wet behind the mounting bracket. So I suspect the sensor or engine head which has oil on it (behind bracket) But that area wasnt cleaned due to access so it could be splashing from the sensor on the engine and down to the ground.

When i took the sensor housing there was a bolt with a plate that spins throught the sensor. Do I remove the bolt and replace an O-ring?? I did a search and checked haynes and it didnt state anything about the bolt/nut. Dont want to unbolt in case it screws up something.