Red hot headers

We just bought a Dodge with a 440, set up for street/strip. No one knew the history-the old man died, car sat for five years, yada yada. But man, what a steal! Has a single-plane manifold and a giant four barrel (and no choke). With a little ether we got it fired up, but it required running it at about 1,200-1,500 rpm or it would die. After five-ten minutes, we noticed the header tubes were glowing cherry red ( it was starting to get dark ). We shut 'er down. Figuring the jets are somewhat clogged and the sucker's running super lean.

Any thoughts??