1. Place upper part as shown on the photo and video.
Note that upper piece can be inserted only as shown.
Lower piece fits snugly, insert rear part first.
Check video for more details.
2. Inserts all bolts and safety nuts, as shown below. No need for washers, for lowest possible profile.
3. Tighten all nuts, in alternating pattern, so bolts are flush with the nuts. Don't overtighten - when lower part meets upper part, it is enough.
4. Place the bike on the footstand and check if upper part evenly fits on the lower part. There shouldn't be any gaps.