I've never removed the parcel shelf and I don't see any job for doing so. I guess I'd start with the rear seats (Group 91) and work from there. Also, 68-449 shows how to remove the C-pillar trim (more plastic tabs). ----Ah, just found it - Job 68-458 R&I of Hatrack. ------
I know what you mean about the old plastic parts that break easily. When I purchased my coupe, many of the plastic trim coverings around the base of the front seats were cracked and broken. But I was amazed that the cost to replace them was not too great...about $10 each piece.
Also, you might find my Index a bit easier to use when finding things in the CDs. You can download it
here. if you haven't already done so. Simple setup instructions are contained in the ReadMe file that comes with it.