[ActionMaxon]

Noise over bumps? Most common component failures are sway bar links and the sway bar frame bushings. That is more of a clunk though, not so much rattle.

Strut tops, control arm bushings, ball joints.

I've never seen a steering rack cause a rattle.

Don't drill into anything in an attempt to add a fitting and grease. Unless you can get out the metal shavings you just created by drilling you're only going to make it worse. When you replace parts, buy ones you can grease if you want that ability. Moog comes to mind.

Rattles come from loose metal like brackets, exhausts, heat shields and whatnot.

Could also be caused by poor installation of new components. Think a shock bolt that didn't get tightened enough. It may become loose enough that a washer is now bouncing around between the shock bushing and nut.

Edit: If you want to add grease to an ungreaseable joint get a grease gun and get the needle looking attachment. Pierce the boot and add grease. Not as effective as a real fitting but might help.