I changed my Nivomate just inside 3 hours. I used the technique to band the shock in the compressed state as mentioned in the FAQ.

Two suggestions:
1. I used perferated metal banding to hold the shock in the compressed state. Plastic tye wraps kept snapping.
2. Jack the car under the spring to compress the shock instead of under the shock. If you jack under the shock, you can't remove the lower bolt because the jack hits the shock.