Thank you for your reply. I am already worried about this. I am not really after the added power here, I just want to replace the exhaust manifolds, which have a hole in them (both sides). So far, I have not been able to find any exhaust manifolds for the car. This is my first classic car, and I was surprised to find there were no replacement exhaust manifolds available for the car. Funny, I remember 1972, and somehow, in my mind I thought there would still be lots of parts available. Rookie mistake there!
I am calling some more places this week, so maybe I'll get lucky. I was planning on using the headers as a last resort in case I can't find exhaust manifolds. Of course, if someone said, that there was a header that was "easy" I probably would have been swayed into attempting them. Thanks for the warning since I have no experience in raising an engine... yet. To tell you the truth, I have never replaced exhaust manifolds either, but I was planning to learn with the help of my friend who is a mechanic.
Wayne