Commodores since VT have seat belt pretensioners. They are a pyrotechnic device actived in company with the airbag, designed to take up the small amount of slack in the seat belt before the occupant of the seat is thrown forward into the belt at the time of a head on prang.
The pre-tensioner is mounted to the inner seat rail of both seats. If you are looking at changing the seats, you would need to see if the seat can be bolted to the existing seat rails or the seat rails with your new seats could accommodate the pre-tensioner.
As these devices comply with Australian Design Rules, deletion of them would make your vehicle illegal in all States, so you can't just ignore the pre-tensioner and delete it for a standard inner belt.
I removed my VY seat last week and noted that the design of the pre-tensioner has changed quite a bit from the VT design, but the principle remains the same.
Regards
pj