No Hassle A-body Headers..... It was done, unbelievable!

Spitfires with a extension tube. Layson's has them. Look "Spitfire" up in search. A bunch of threads about them.
Appears they were more designed for early A's. I've never owned an early A. For sure not the optimum for performance, but a really nice fitting header that will certainly outflow a manifold. I don't know who did the extensions, but they drop down real convenient for the collectors. I was just amazed at the installation for the drivers side. Of course, the car I tried the drivers side is a '74 with manual steering.