I hqve a complete TTI exhaust system on my W2 67 Barracuda. It is more work than stock heads as the prmary tubes are 1 7/8". If you don't want to cut tubes to get the right fit, then use the H pipe system. I don't think there is much diference on a street car. The X pipe has mutiple pieces between the header and muffler because of the X. Once I layed it out and READ the instructions, it went right on.