Gentlemen, I haven't been around lately, but Kurt asked me to comment so here's the breakdown:
Standard interior (without console) - black (textured) dash panel and black (textured) ash tray
Standard interior (with console) - woodgrain dash panel and black (smooth) or woodgrain ashtray (see Transition notes below)
Z23 or Z87 interior (without console) - woodgrain dash panel and black (smooth) or woodgrain ash tray (see Transition notes below)
Z23 or Z87 interior (with console) - woodgrain dash panel and black (smooth) or woodgrain ash tray (see Transition notes below)
Note that all 1968 woodgrain dash panels are verticle pattern. The horizontal pattern is 1967 Firebird.
Transition:
Black Woodgrain Notes
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Thru 01B LOS/NOR n/a early black only
01C-02B LOS/NOR LOS/NOR early transition
02C-03B NOR LOS/NOR late transition
03C-on n/a LOS/NOR late woodgrain only
Ed