One of the areas of tech that always proves hard to deal with is the annual tech and regulations for vintage race cars. It's a two-fold argument, but the picture I'm including in this post proves the point far more than anything I could say.
Often, the rules for vintage cars for annuals are more "lax" in some areas, because the general thinking is that there should be as little modification to the race car as possible in order to not harm its historic significance or its value. I can't disagree with the thought, except that there are certain areas where we have learned valuable lessons since these vintage cars were originally built.
I have heard all kinds of arguments against changing roll hoops and cages in vintage race cars, including the "must keep it original to the period" argument. Here's why I don't buy it and I hate signing off on a vintage car with a roll hoop or cage that makes my gut clench.
The assumption that "It's just vintage" or "The 13/13 rule means this isn't an issue" is just that - an assumption. It's not a fact or a reality.
If it has a cage or a roll hoop on it, then that cage or roll hoop should be brought up to current day standards. If it doesn't have a cage or a roll hoop, why would anyone even let it out on a race track?