Kawai PN90 Owner's Manual page 5

Side view Rear view
(B)
NOTE:
3. Hold (B) behind (A) and (C). Fasten
(A) and (B) with four screws (H) and
with three screws (G).
4. Place the piano on the stand. Then, slide
the piano backward to place it at the
appropriate point for screws. Hold the
piano on the stand so that it doesn't fall
from the stand. Then fasten the piano and
the stand with four long screws.
CAUTION: Be sure to secure the piano
to the stand with the screws. If you fail
to do so, the unit could fall from the
stand causing damage or personal
injury.
5. Insert the pedal connection cord that
comes from Pedal Board (C) into the
piano's pedal jack and fasten with clamps
6. Turn the adjuster (installed on the
bottom of C) until it touches the floor to
support the pedal board.