Shrunk a picture down and added. Also deciphered most of the RPO codes in the glove box using a couple online decoders:
http://www.rpocodes.com/https://www.crankshaftcoalition.com/wiki/RPO_(Regular_Production_Option)_GM_master_listA01: Tinted glass
A52: Custom Deluxe vinyl front seats
B84: Body side moldings
CMD: Plant code for Flint, MI
C60: Air conditioning
C7A: GVW 10,000
C91: Dome lamp
D1Y: Gear driven speedometer
D45: Stainless low mirrors
E6P: ?? Country of Gibraltar ??
E6J: ?? Country of Puerto Rico ??
E9Z: Speedometer key (delete)
GT5: 4.10 rear axle
G60: Main and auxiliary rear springs
JB8: 10,000 lb brake equipment
K19: Exhaust emission control
K22: 94 amp alternator
L19: 7.4 TBI engine (454ci)
MM4: 4 speed manual
M20: 4 speed manual
NA5: Standard emissions equipment
NL2: Auxiliary fuel tank
R05: Dual rear wheel conversion
SLM: Stock order, processing code
TT4: Headlamps, 4 halogen
UA1: Heavy duty battery
UF2: Cargo area lamp
UN9: Radio suppression equipment
UP8: Stereo radio
UU9: Radio, AM/FM ETR
U73: Fixed mast antenna
V22: Deluxe front chrome grill
V73: Vehicle statement USA/Canada
XDL: ?? tires size ??
YDL: ?? tire size ??
YD3: Front axle
ZN3: rear axle ratio?
ZW9: Base cab and chassis
ZY1: One color solid paint
12U: Primary color silver metallic
77I: Interior trim color, light medici red
77W: Trim combination (dark maple)