Let’s see, heat up and bend a vital steering component, thereby changing your steering geometry and possibly the strength of the pitman arm. Or put a small dimple in the header, changing nothing.
He still haven’t even exhausted all the options yet. Shimming the engine mount is easy. Buying a new pitman arm to match the idler arm and possibly replace a damaged part is easy. And either one of those options could solve the clearance issue. And if not, a little dimple there in the header won’t hurt a thing.