[PbFut]

Yup, tried a punch and ripped the plug at the shaft. Got one installed but had small rip. Posted above question. Then occurred to me to make the plug section smaller. Using a harbor freight copy of a Dremel benchtop belt sander, I took just a tiny bit off the edge of the plug portion of the bumper. Effectively reducing the diameter of the portion you push into the hole. It was very little. I expected i would need a second pass as i wanted to creep up on the needed change. First pass fixed the problem.
I still needed a nylon trim tool to work the plug into the hole, but it was like I would expect the part to fit. It still feels rock solid in place so I know the application is not compromised. Of course a dab of Presision rubber lube is a must.