Only runs 40 Degrees advanced

Wow ok so you have basically eliminated most everything except cam timming so I'm going out on a limb here but is it possible your cam "twisted" when the dist locked up and now some of the cylinders are out of phase? do you have a old junk cam and lifters around you could throw in just to see if it made a difference?
Cams don't twist, they break. The gear would strip or the little drive shaft would shear well before the cam would ever get damaged!