The speaker is mounted on the top cover. The cover can be placed with the speaker in the front or back side of the case.
The speaker is fitted with two clamps to hold it,carefully place clamps on the sides of speaker and use the screws provided.
Solder 2 PIN relimate connector wire length as per your needs.
Normally do not cut the wire and keep it as it is . In the picture a short wire is used as it had another half on the board which was mating with this wire, since you would be using a single connecting wire so do not cut it,
So that is it for the speaker connection and placement on the top cover of the ubitx universal case.