I have a 91 RS Convertible, black, that I bought new as a 2ndLt in the Marines. It's IMMACULATE....except for....of course, the dash, which warped and shrunk and cracked and all the stuff they did during this year group. Well, for 15 years I searched junk yards, online, used car lots, wherever I could when I had some time to try to find a replacement. I contacted parts manufacturers, dash cap makers. I contacted GM. I used a cloth dash pad. I finally cut the top of the dash off and built a new surface using layers of fiberglass screening etc. Years ago I gave up. Then, just three days ago, I'm driving 1/2 mile from my house and right there, before my eyes, a 1994 Z24 for sale in some dude's yard. Looked terrible. Purple car, one replaced door. Faded paint, cracked hood, peeling bumpers, drooping headliner, moldy and smelly interior, broken window......AND.............PERFECT DASHBOARD! Sale price.......$200!!
The dash on the 94 RS was perfect when I got and still is. I use a sun shade religiously on every old vehicle I have. Swapping out that thing is big deal. Ironically I have had to replace the heater core in a 3rd gen and found that dash, while a lot of work wasn't as daunting at the earlier versions.
Just be super careful and take your time. A couple of helpers would be invaluable. Getting the good one out without busting it will be just as hard putting it back in your driver! Hope all goes well!