the JSC has the original SFX
That’s good info too, thank you!
I’m now mostly using the '85 LDs as a reference for reconstruction and only matting in tiny elements of that stuff into footage from 4K77 and D+1977. So far, the '85 LD footage is OK for now. Fullscreen JSC might be a better copy than the US '85 and thusly more usable as-is. This might merit a return visit at some point.