I have had and seen plenty of 69s with the Reinforced Shock to Cowl Braces. Not all 69s used them(unsure of reason why some did and didn't, maybe an early vs. late thing?) but all 1970 cars apparently did. I agree, the date codes are to new for your 9/19/68 Car. I don't believe any other cars used this style brace besides Mustang-Cougar so I don't think that could be an 'O' Stamping Plant on them. I posted to your same question over on CJ and I also have seen the D inside the O that Jeff mentioned. Kinda looks like this (D) and I have had tower braces with that style (D) stamp.. Maybe repros that someone stamped? I remember when I was a kid my dad had a Die Stamp Set that I would use to stamp my initials on the bottom of my bicycles in case they were stolen, so the stamps are available. Andrew