headers or not to headers

I just finished putting a set of TTIs on my son's 70 Dart 340. They were a huge pain to install. Pulling the steering and unbolting both motor mounts wasn't a big deal, but physically getting them into the car was a pain. My son's car does have power steering and brakes, this made it harder I'm sure. Spark plug and valve cover clearance is much improved over the 340 manifolds. I installed a remote oil filter, because it was a pain to remove in the first place. I wish I had put a mini starter in at the same time. We changed out the 340 manifolds because the were cracked and leaked bad. The TTIs are very good quality and do have more ground clearance than the cheaper headers. For a street car I would go with new stock manifolds. For a race car I think I would use fenderwells.