Dont think this will make you feel better,but reality is that the only way to be sure a header fits right the first time is to build it yourself in the first place,these cars are absolutly horrible when it comes to production tolerances,they are all over the map so to speak,add 40years of wear and tear,use and abuse to the equation and you will be pretty close to the perfect storm. i dont think TTI are perfect,no manufacturing bussines is but they are very good in my opinion even if its almost hopeless to make a good product for these cars.