Was looking at a 3 point racing harness and was thinking if I could still use two points, i.e. have the 3 point connected to a safety wire that is connected to the two points which is behind the seat, therefore the chassis should be strong enough and no need to drill new holes. What do you guys think?

 

I don't really understand what you're talking about, so it might help if you could explain a little more. That said, anything with 'safety wire' and 'seat belt' in the same sentence is a bad, bad, bad idea.