IMO I think the trunk finish panel "red" should match the dark red of the tail light lens during the day. I (my opinion) think that's what was intended but didn't always happen by restorers or originals faded over decades to a brighter red.

This is my '68's rr's trunk finish panel after it was restored by someone that was, at the time, considered one of the better restores of finish panels and trim work. While he had it I emphasized the fact that I had three other originals that I had collected and they were all dark red or maroon in color and that more research that I had done seemed to confirm the original color was a dark red or maroon. I got it back and IMO it was too red and not dark enough. I was p!$$#d but nothing I could do as I waited, and waited an extremely long time to get it back from this person.....and he is no longer in business. The color should mimic the tail lights so it looks like they are completely surrounding the finish panel. Kind of like the old Thunderbirds and current Charger and Challenger, etc.,

Mike