They do have relevance as for some Sandmans you could not order metallic paint easily on non-Sandmans. Those 4 x digits on the TRIM line are the paint colour, the stuff on the paint line is irrelevant - that is for aftermarket repair use as it is the paint maker's code.

You can tell what stripe colour a car had by the paint combination. The important thing you cannot tell for a HZ is if it had stripes or not. DL7 (delete stripes) was a very popular option. My guess is there would be more DL7 HZ's sold new than any other stripe colour.