I used a wafer wheel on a Dremel to carefully remove the punch marks so I could get the plugs out and again to clean them up, to get them back in. Once I was sure that they were seated, I expanded them with the hammer side of a ball peen (as klhanson stated), then used a center punch to peen over the edges in four spots.
Last edited by Phak1; 08/06/2021 7:51 PM.