Check this as well - If I'm not mistaken, the handgrip/control assemblies each have a small locator "bump" that fits into a hole on the OEM handlebars so that they don't rotate. If you have aftermarket bars, they might be 7/8" but might not have the hole in them. if you take a look at the inner rounded part of the controls, you can see if there's a bump, and if your handlebars are missing a hole. If that's the case, you can drill holes in your new bars to make sure the controls don't rotate.
When you drill, I found it helpful to cut a little cross-hatch with the edge of a file, then the drill bit could bite without rolling off the side.
My NH had the little nibs in the controls damaged. To keep the controls from rotating on the bars, I used a scrap of bicycle inner tube around the bar so the controls would grip when tightened. But you won't need this is your control nibs are still good.
