possible oil cooler leak?

[stoney126]

hey all, going to start doing some needed fixes on my truck. one of which is an oil leak. I cant tell if its the oil cooler or not. I imagine i should probally start from the top down but I thought id show a picture and get some input

[stoney126]

Nothin? Ok how bout the best way to clean my engine as to help identify the leak source

[alpipehand]

cpl cans of engine degreaser..just follow instructions on the can