440 under car headers need advice.

Money no issue. Have em built. Insist on equal lenght. And spark plug access. Then stop by often to watch progress and learn why they cost so much.

Very true. I just helped a friend build 2. and 1/8" headers on a Super Stock 68 Mustang with a Windsor engine. Incredibly time consuming. IDK how much he charged his customer but he paid me plenty for all the time I put in so I'm sure they were very expensive.