Savaria Toyota Sienna Owner's Manual page 13

To remove the front retractor, lift the lock plunger and slide the
fitting in either direction along the track while lifting the assembly
out of the track.
3. Once the retractors have been fastened to the track, attach the
J-hook on the retractor webbing to the front of the wheelchair
frame. The front securement point should be positioned as high
as possible on the wheelchair frame for maximum safety as
recommended by the wheelchair manufacturer. Refer to your
Q'Straint Instruction Guide for ideal fastening geometry.
Refer to your wheelchair manual for instructions on selecting the most appropriate
wheelchair securing locations.
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