Thanks for the help Jonno! :D

I think I am almost finally at the stage where I am able to say the revised NTSC DVD of Star Wars is finished, I say almost because I still need to watch the DVD all the way through to double check it. I have run the DVD through DGIndex and it didn't flag up any errors so hopefully this is a good sign! I have done a reversal of sorts this time around where previously I concentrated on the PAL DVD and then did the NTSC one as an after thought, this time around I am concentrating on the NTSC DVD in the hope that if I get it right then the PAL DVD should be a doddle.

As the lack of a layer-break point caused some issues before I have found I can use PGCedit to create the ISO, which allows me to set the layer-break point. :D So hopefully that wont be a problem this time around. I have also adjusted the white levels in the colour grade compared to before removing the luma curve adjustments I had made to the whites and lowering them.

From looking at the waveform for the Luma of both the GOUT and THX WOW DVDs it seems the GOUT waveform has had a lift of about 10 IRE applied to it which would explain the clipped whites and washed out blacks, so I have kind of reversed this lift which should put the levels back roughly where they should be, the whites are still clipped but there's nothing I can do about that. :(

I am hoping to have Star Wars finished by the end of the week so that I can get back onto Empire. ;)