Trim

The 6th box from the left on the top line indicates the Trim code. My friend Veronica Sczbecki has upholstery samples on her May 3, 2008 Blog post: The Care and Feeding of Ponies.
http://thecareandfeedingofponies.blogspot.com/2008_05_01_archive.html
Veronica also has a lot of other good information about 64.5 thru 66 Mustangs! 
And Klaus has some good interior photos on his Early Mustang site:
http://www.early-mustang.com/modules.php?name=Content&pa=showpage&pid=21&page=2
Standard trim codes with an "A" following the numbers indicates upholstery with no Rosette material in the seat cushion and back. Deluxe trim with and "A" following the numbers indicates the quarter trim panel was a one-piece design.

TRIM

22	Bucket – Standard – Blue w/Rosette	62	Bucket – Deluxe – Blue & White
22A	Bucket – Standard – Blue	62A	Bucket – Deluxe – Blue & White -1 pc. Qt.
25	Bucket – Standard – Red w/Rosette	64	Bucket – Deluxe – Emberglo & Parchment
25A	Bucket – Standard – Red	64A	Bucket – Deluxe – Emberglo & Parch. – 1 pc. Qt.
26	Bucket – Standard – Black w/Rosette	65	Bucket – Deluxe – Red
26A	Bucket – Standard – Black	65A	Bucket – Deluxe – Red – 1 pc. Qt.
27	Bucket – Standard – Aqua w/Rosette	66	Bucket – Deluxe – Black
27A	Bucket – Standard – Aqua	66A	Bucket – Deluxe – Black – 1 pc. Qt.
2DA	Bucket – Standard – Parchment	67	Bucket – Deluxe – Aqua & White
D2	Bucket – Standard – Parchment Rosette w/ Blue	67A	Bucket – Deluxe – Aqua & White – 1 pc. Qt.
D2A	Bucket – Standard – Parchment w/ Blue	68	Bucket – Deluxe – Ivy Gold & White
D3	Bucket – Standard – Parch. Rosette w/ Burgundy	68A	Bucket – Deluxe – Ivy Gold & White – 1 pc. Qt.
D3A	Bucket – Standard – Parchment w/ Burgundy	F2	Bucket – Deluxe – Parchment w/ Blue
D4	Bucket – Standard – Parch. Rosette w/ Emberglo	F2A	Bucket – Deluxe – Parch. w/ Blue – 1 pc. Qt.
D4A	Bucket – Standard – Parchment w/ Emberglo	F3	Bucket – Deluxe – Parchment w/ Burgundy
D6	Bucket – Standard – Parchment Rosette w/ Black	F3A	Bucket – Deluxe – Parch. w/ Burgundy – 1 pc. Qt.
D6A	Bucket – Standard – Parchment w/ Black	F4	Bucket – Deluxe – Parchment w/ Emberglo
D7	Bucket – Standard – Parchment Rosette w/ Aqua	F4A	Bucket – Deluxe – Parch. w/ Emberglo – 1 pc. Qt.
D7A	Bucket – Standard – Parchment w/ Aqua	F6	Bucket – Deluxe – Parchment w/ Black
D8	Bucket – Standard – Parch. Rosette w/ Ivy Gold	F6A	Bucket – Deluxe – Parch. w/ Black – 1 pc. Qt.
D8A	Bucket – Standard – Parchment w/ Ivy Gold	F7	Bucket – Deluxe – Parchment w/ Aqua
D9	Bucket – Standard – Parch. Rosette w/ Palomino	F7A	Bucket – Deluxe – Parch. w/ Aqua – 1 pc. Qt.
D9A	Bucket – Standard – Parchment w/ Palomino	F8	Bucket – Deluxe – Parchment w/ Ivy Gold
32	Bench – Standard – Blue	F8A	Bucket – Deluxe – Parch. w/ Ivy Gold – 1 pc. Qt.
35	Bench – Standard – Red	F9	Bucket – Deluxe – Parchment w/ Palomino
36	Bench – Standard – Black	F9A	Bucket – Deluxe – Parch. w/ Palomino – 1 pc. Qt.
C2	Bench – Standard – Parchment w/ Blue
C3	Bench – Standard – Parchment w/ Burgundy
C4	Bench – Standard – Parchment w/ Emberglo
C6	Bench – Standard – Parchment w/ Black
C7	Bench – Standard – Parchment w/ Aqua
C8	Bench – Standard – Parchment w/ Ivy Gold
C9	Bench – Standard – Parchment w/ Palomino