Hello.
Welcome to the forum.
I think someone has added a piece to that tow-bar. Probably to fit a stabiliser. If so you won't need that piece.
The main towbar fixing on a 240 is two large bolts. They are longer versions of two bolts that are part of the car without the towbar. You can access the bolt heads from inside the car. If the car still has the original bolts you can get longer ones of the same quality specification from your usual fixing supplier.
Later 240s use also some smaller machine screws. I see your towbar has those smaller holes. The car typically has tapped holes for those screws. Again, your usual fixings supplier will almost certainly be able to supply.
I apply copper based grease to tow-bar fixings threads.
The 240 is a superb tow car.
Stephen
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