Buick Interior trim codes are identified on the trunk SPID label and they always start with two numbers.
The first two numbers are the basic color and the third will denote what part of the car the trim code is for.
For example on a Regal Grand National the code 82I means the medium gray basic interior color with the I standing for Interior and the code 82C which is for the seat color and material type.
1984 Interior Trim Codes
22 Dark Royal Blue
67 Dark Briar Brown
77 Dark Maple
42 Medium Gray Fern
60 Light Sand Gray
61 Medium Saddle Tan
1985, 1986, 1987 Interior Trim Codes
27 Dark Blue
43 Medium Sage
62 Light Saddle
79 Dark Claret
82 Medium Dark Gray
Codes ending with the letter I denote basic interior color.
Codes ending with the letters B-C-D-E-G-H-J denote cloth and vinyl door and seat trim
Codes ending with the letters N-R-V-W-Y-Z denote all vinyl door and seat trim
Codes ending with the numbers 2-3-4-5 denote leather seat trim
Any other codes on the label are to be considered internal assembly plant codes and have no significant importance.