Rocker Arm Ticking vs Fuel Injector Ticking Noise

[lutey]

I'm trying to distinguish between regular fuel injector ticking noise vs eminent rocker arm failure noise. I've searched youtube.. and there is plenty of videos on rocker arm failures and the ticking noise, but even on relatively new penestar's you hear some fuel injector tick (or other valvetrain noise). Is it just a trained ear that can tell the difference, or is the noise from a specific location. I'm going to be purchasing a used JK Wrangler (a 2015 or later), and need some help identifying engines with rocker arm issues.

Thanks for your time !!