Track cars

I'm hoping we have some track car experts can help me out. Now I have someone who is making a track car from an old series 3 BMW and as part of this he has a new tiny steering wheel with no airbag of course. When he's done he wants me to test it. As we all know the lack of airbag is allowed if it's properly converted to a track car, but I don't actually know the details of how much needs to be done. I thought it's going to need a roll cage at least, but he says he's having a half cage fitted, just in the rear. I haven't been able to clean the details from the manual and guide, so I'm going to rely on you guys.