What is the correct installation procedure for securing a wheelchair passenger using a certified 4-point tie-down system (4-Punkt-Rollstuhl-Rückhaltesystem) in a passenger coach?

1. Attach two straps to the front wheels and allow the rear of the wheelchair to float freely
2. Anchor the four heavy-duty tie-down straps into the vehicle floor tracks at approx. 45-degree angles, attach them to structural frame members of the wheelchair (not plastic footrests or quick-release wheels), tension firmly, and apply the wheelchair wheel brakes
3. Fasten a single bungee cord around the passenger's chest and connect it to the overhead luggage rack
4. Wedge the wheelchair between two rows of passenger seats without floor track tie-downs