1983 GMC Option Codes

[67RS/SSx2]

Is there a place I can find option codes for a 1983 GMC? My 1983 Sierra Classic 2500 crew cab is now on its way to me and I'm trying to figure out exactly what I'm getting.

I have some paperwork from the original dealership (General GMC in Phoenix) that show its option codes. I have some questions. What I know is

G01010.....R. AXLE STANDARD
MX1020.....3-SPD AUTO TRAN
ZY4020.....DLX2 TONE PAINT
21L050.....21 BLUE 29 BLUE

Now my questions.
1) Is this rear axle a 3.73? Elsewhere I have paperwork with a hand-written "3.73". This truck has the 5.7L engine.
2) Is this the TH350 or TH400 transmission?
3) The truck is now a single color (or at least appears to be so). What would this 2 tone paint scheme look like?
4) What blues are these (example pics would be great).

Can't wait for this thing to get here.

Only down side is now I have to sell my 72 C10 Cheyenne Super.

Oh yeah, !