vhs-bordercontrol, telecide() and (ml)degrain in vapoursynth

[i4004]

regarding these 2 remaining issues to process vhs sourced mjpeg.avi:

-avisource in hybrid (vapour or avisynth mode) doesn't seem to work, even with ticked checkbox (filtering->vapoursynth>misc. prefer avisource), it still defaults to other loading methods (ffmpeg and libav)
but this can be ameliorated if one converts mjpeg.avi to ffv1.avi prior to processing....
(vapour lost ability to do avisource with abandoning of 32bit version, it seems, so now one has to......oughm....port avisource from avisynth+(64bit)? dunno....seems like a rabbit hole)

-would it be possible to add something like this

clip=core.std.Crop(clip=clip, left=0, right=0,top=0, bottom=12)
clip =core.std.AddBorders(clip=clip, left=0,right=0,top=0,bottom=12, color = [0, 128, 128])

to hybrid's "frame" options (vapoursynth filters), as all other filters on that tab don't seem to be able to just cover vhs headswitching noise on the bottom of the frame with black borders.....offcourse adding black borders on all four sides would be a plus....
(if it's not too much of a hassle to add it)

thanks