Yeah, I'm running fenderwell headers, so header clearance wasn't really a concern for me. I have a 70 340 Dart Swinger - and I am also running the later steering and brakes on that car. The small block TTI's rub ever slightly on I think the passenger side where the idle or inner tie rod is. I built the car in the early 2000's - and just let it rub and clearance itself! Not sure how the Big block TTIs will be for you.