OK, thought I had better finally update this, in case anyone is interested!
After a lot of umming and ahhhing, I decided to bite the bullet and screw the trims down, to sort out the gap between the card panel and the bottom of the side windows. I used stainless steel screws in screw cups, and pleased to say 3 screws on each panel brought them down into line and didnt look all that out of place either. RESULT.
The issue I had then was the condition of the cards themselves. One had a hairline split, and the other a slight tear from pulling the rear seat out once. Both were pretty minor, but had been bugging me for some time.
I ended up getting 2 meters of Vinide rexine in British Racing Green from a place called Martrim in Sandbach. It was the closest I could find in terms of colour match and embossed pattern. I set about removing, cleaning the cards up and of course covering them in the new vinyl. This is not a particularly easy task, the new vinyl does not take well to dips and curves, I can only surmise that when they were first "made" by Vauxhall, they were vacuum formed, as the original vinyl is certainly more plasticy, and stretched into place.
The only real loss is that the original cards were two tone, and now they are all one colour. I actually prefer it this way, but would lose points with the purists! After a lot of spread glue and manipulation, I finally got them done and back in the car, see attached picture. They are not perfect, but I am happy with the outcome.
All told, it cost me around £70, a lot of work, and all to solve a few things that no sane passer by would even notice
Still, that's all part of the fun, isn't it.....?? Apologies for the quality of the pic, the light was going by the time I got finished...
EDIT: She is also 48yrs old today!