Lots of different opinions on this subject.
My headers were cheap. I did not wrap all of them, just the areas that are near the starter.
Much of the header on the right side is not wrapped.
It would take a long time for the wrap to damage the headers.
Takes hardly any time at all for the HEAT to damage the starter though.
I think my biggest problem was choosing an offset gear reduction starter.
This configuration seems to place the starter motor itself closer to the header tubes.
I have decided to just get another starter and replace it. I will go with an IN-LINE starter this time. I might even spring for a Tilton, not sure yet.