Cm2250 oil leak driver side behind air compressor?

[jimeneztrans84]

Did a good pressure wash on driver side of the engine and made sure compressor bolts were tight. Still can't seem to figure out where that oil leak behind compressor is coming from. I'm thinking maybe gasket it toast? Anything else to check for? Pretty hard to see between compressor and engine too.... that oil leak is driving me crazy!! Also truck has original compressor and 581k miles.