Alan, you're probably better off getting the parts from salvage, as they'll be quite cheap I would have thought.
Spike, the ashtray is covered in detail; take a look at illustrations 857-00 and 857-30. Yes, I know that there are differences between the drawings and actuality, but they show all the relevant parts that are replaceable. Obviously the lights and clips are not shown as they are integral parts.
The wiring of the lights is via a small 2-pin connector that attaches to a clip on the back of the ashtray.
Cheers,
Mike