The new "production" track brace coming in on track pack cars is lighter, simpler and cheaper than the first version. I think that the first version may have come out of a different part of the company, Lotus Sport, but I'd have to check on that.
From the horse's mouth the new brace is a simple steel tube with a hole drilled through each flattened-out end. So the bolts that goes through the accompanying new rod ends would also pass through one end of the track brace. The feeling is that the stock bits are fine for A048 tires it seems. But if you go gummier, then you should add the brace. Adams seemed to indicate that, for autocross, the brace was not really necessary, even on Hoosiers, not sure about Goodyear "real slicks". Must be a time duration thing as autocross is so brief compared to a series of 20-30 minute runs at a track day?