Working on a Case-IH 1063 corn, replacing the bushings in the aluminum gathering chain tightener guide blocks and am thinking about drilling and tapping them for grease zerks. There are 4 bushing per gathering chain but it seems like the bottom ones are the only ones that wear much, so I would probably only do 2 zerks per chain. I am not sure how easy the zerks would be to get at after the row dividers are on. Anyone ever do this?