Blake,
My TA22 is 1973 and is legally engineered for Harness's. I could only get a half cage legally passed ( a 6 point cage is basically just not legal in NSW anymore altho I do know an engineer that will pass them) and of course the car is legally registered as a 2 seater. The Harness had to be fitted to the stock seat belt mounting points and had to be ADR compliant. They are a seabelt 3 point. There are very few ADR compliant belts but you get them and use the stck mounts and you should be sweet
I strongly recommend trying to get your ticket from a legit engineer such as John at consulmotive, As Stew has mentioned, when push comes to shove, Legal and Engineered are not the same. My RA28 was not done by John due to some time restrictions BUT everything on it will pass if I every need to get re-ticketed.
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