This looks like a Lynch Road (Detroit) build plate. Starting at the bottom as line 1:
line 1
0312 = March 12, 1964 build date
0321 = shipping order #
345 = Sport Fury convertible
P4B = premium bucket seats B = blue
EE = dark blue iridescent (metallic)
line 3 & 4:
AB 14 = 365 h.p. 426 Street Wedge
C 3 = 4-speed Manual trans (option # 343)
E 4 = Deluxe steering wheel (option # 414)
G 3 = AM/FM radio (option # 363)
J 5 = heater and defroster (option # 365)
N 3 = backup lights (option # 423)
P 8 = dual jet windshjeld washers (option # 428)
Q 1 = sill molding (option # 471)
R 2 = left outside remote control mirror ( option # 482)
V 2 = sold to customer order
Z 5 = ?
line 5 & 6
12 06 = gate number
567 115 = base sequence number
If you look at the alpha/ numeric combos on lines 3 & 4, the numeric part is always the last number of the option code. Date codes are kind of self-explanitory from January (1) through September (9). October becomes (A), November (B), and December (C).