I'm no expert, but I seem to agree with you on this one...I don't recall a Trim 727 code for X33 other than the 711 and 712...Here is a cowl tag number from another post that I searched before I responded..
02D = Built the Fourth week of February.
69-12437 = Coupe.
NOR = Built in Norwood Ohio.
727 = Standard Ivory/Black Bucket Seats.
50-B = Lower Color is Dover White and the Vinyl Top Color is Black.
X11 = non-SS396, non-Z28, with style trim