EdFarmer said:

Okay, took some extra time to look a bit more closely at the Lucasfilm logos, and it does look like a different font. But it was helpful to take a closer look because it looks to me like the SW Lucasfilm may be using the same font (though capitalized and more rounded) as the ALTA.

I doubt it - as I said, the LFL font looks to be Univers, which (to give one example) has a completely different shape of lowercase "g" than the ALTA font.

Apologies if I'm restating known information, but the ALTA font (which seems to also be the credits font) is a customized version of News Gothic - it's not the same as the current commercially-available version for computers. (In fact, I'm not sure if the official version of News Gothic at the time was same as the modern digital version, either.)

If you look at the hook on the top-right of the "g", the current commercial version is different. Also, Mike Verta says that the "x" is horizontally flipped compared to the official News Gothic. (The current News Gothic has a lowercase "x" with equal sides - apparently, the News Gothic of the time had an asymmetrical "x", like the one in the modern News Gothic Condensed.)

There's still some more work that has to be done to get your version to match the original, but you're doing a great job so far. I'll PM you about it.