Editing/merging TFF and BFF interlaced MPEG-2 files together?
 

I'd assume that this isn't possible, but thought I'd just make a thread anyway and to get other, more knowledgeable opinions. I have two MPEG-2 files. One is sourced from a retail DVD, the other is sourced from a VHS tape I captured (Panasonic NV-SB900 -> TBC-1000 -> ATI600 USB) to HuffYUV AVI, then converted to MPEG-2.

(For reference, this is an episode of Power Rangers Time Force (2001). When 9/11 occurred, a number of episodes were edited, and the original, uncut aired versions were never broadcast again. For the DVD release, the pre-9/11, uncut masters were sought out but could not be found, so the edited masters were used for the DVD release.)

I'm attempting to combine the much better quality footage from the DVD release with the VHS footage I've captured to create an "ideal" representation of the original uncut episode. However... when I use GSpot to analyze the episodes on the DVDs, it shows they are BFF. (This confuses me, as [I believe] it should be TFF, but the picture looks normal and it doesn't appear the field order was reversed.) My VHS capture is TFF, as it should be, and here lies my conundrum:

Is it possible to edit these two files together? If not, is there some way I could convert one or the other?

Thank you!

Yes it's possible, but since your capture is lossless it's far easier to just transform it into BFF to match the lossy source instead.

There are several methods in Avisynth; this is my personal preference:
There's nothing inherently correct about a given field order.

Mixed BFF/TFF is common for satellite feeds, and it's horrible source to work with.
Switching it is best --- or even deinterlacing entirely if you must (QTGMC in Avisynth).