I too use the TechnoVersion mount on my R200 race car with the black snubber and stock OE mount. I can't comment on the NVH since it's a race car, but I will say that it is much easier to install the RT mount with the diff removed. I did it with the diff still in the car and it was a terrible job. There simply wasn't enough room to get it into place. Again, since it is a race car, I wasn't worried about scratching the paint on the mount or the tunnel and I eventually got it into position, but on a street Z, I would never do it that way again. I would remove the diff and then fit the RT mount. I likely spent way longer than if I would have just dropped the diff in the first place. I think I cut three tiers off the snubber, but I can't remember for sure. It's been a few years since I did it.