I Googled 429 Ford shorty Headers.
Ford Powertrain Applications shows some shortys, for several applications.
Not for a 63 Fairlane though.
I would say that your car has had the shock towers cut and reinforced like the Thunderbolt. I would think that one of there Headers would work for you.
Give them a call. I've never bought anything from them myself. Have heard of people using their products and very happy with them.
Jet