'86 560SL problem"

My airbag is rattling when I ride over bumps and holes and I think I need to either tighten the torx screws that hold the airbag to the steering wheel or take the airbag off and replace a bracket or two.

Before I go out and buy a full set of torx bits, can anyone tell me what size I need to tighten/remove the screws?

Thanks, Ryan