I have one of the fussiest cert guys around and never have issues with the work we have completed on the vehicles with most of my conversions going straight through. My conversions are some of the tidiest around and most look factory. If your guy wants 4 bolts then you will have to do as he says. It becomes his responsibility when he certs it. In some conversions the hoops get welded into cross members and I work on the theory that if I think its safe, that it is a item I would have in my own vehicle and it is well made then it's ok. Working this way I have no issues with my workmanship. And I do heaps of conversions too. Cheers