EX in group 1 is tinted and power windows
group 2
K ~ Air conditioning [RPO C60]
M ~ Powerglide transmission [RPO M35]
P ~ Comfort & Convenience Group (Type A) [RPO Z01]
I can't find a "G" reference anywhere. this a Baltimore car, right? Can you scan the build sheet?
(maybe "G" is for "custom" door panels?

)
How about auto load leveler shocks
here are the engine codes, they don't show a listing for an L79 with an auto.
EA 327-4 250-L30 Manual-3/4
EB 327-4 300-L74 Manual-3/4 High Perf, AFB Carb
EC 327-4 350-L79 Manual-3/4 HD Spcl. High Perf, Holley Carb
ED 327-4 350-L79 Manual-3/4 HD Trans Ignition, Holley Carb
EE 327-4 250-L30 Powerglide
EF 327-4 300-L74 Powerglide High Perf, AFB Carb