Technical question on "mild cam"

Pull a valve cover off and look for adjustable valvetrain. If someone stuck a solid cam in it, and it needs lash adjustment then adjustable rockers will be there. If it has non adjustable factory type rockers then the chances that it has a hydraulic cam in it is about 99.9% and won’t need adjustment. But I have a question for you, you said “the engine runs great, currently…”. If that’s true why are you tearing it down?