Thanks all! hah. if I can replicate the PaNup process with Avisynth (on a VMware install, however) I’d go that route.
Since I’d use the original NTSC audio and re-sync the language tracks from the PAL discs, I suppose it’s a matter of getting the sources synced at 24fps first. What’s the slickest way to get that done? Shot by shot as an image sequence?