How do you lube your 5th gen doors?

2002 Max.. At the front of the doors near the hinges, is a black plastic thing that slides in&out of the door. Is there a proper way to lube that thing without making a mess?

My 93 had metal, which was easy, as you could just slide some grease between the metal plates. but the 5th gen is just a solid plastic rod... should I just slather some grease all over the outside of it? Messy!

Or does this plastic version somehow get greased on the INside???

Thanks!