If you go to this web site:
http://www.mymopar.com
and click on the 'Tools/Reference' section (menu on the left), you will find a link to the PC Fender Tag Decoder in the second column, third row.
Here's the link :
http://www.mymopar.com/downloads/decode.exe
You can then use this to decode your own tag. Problem with this program : you can't copy the results, or save to a text file.
You can also use an online Fender Tag Decoder, such as this one :
http://www.stockmopar.com/mopar-fender-tag-decoder.php
Here is the result (web ste designer apparently likes to write 'Bottom' with 3 'T's):
Decoding of Fender Tag: Botttom to Top, Left to Right
Code Description
JS23 J = Dodge Challenger
S = Special
23 = 2 Door Hardtop
N1B N = 383 300HP 1-4BBL 8 CYL
1 = 1971
B = Dodge Main, Hamtramck, MI, USA
411164 Sequence Number '411164'
Decoding of Fender Tag: Botttom to Top, Left to Right
Code Description
E55 340-4 Barrel 69-73
D32 H-D A-727 TorqueFlite Trans / Some Years A-998
JS23 J = Dodge Challenger
S = Special
23 = 2 Door Hardtop
N1B N = 383 300HP 1-4BBL 8 CYL
1 = 1971
B = Dodge Main, Hamtramck, MI, USA
411164 Sequence Number '411164'
GA4 Paint Code: Unknown At This Time
H6X9 Trim Grade/Style/Color
H = High
6 = Vinyl Bucket Seats
X9 = Black
000 Upper Door Frame: Full Door Panel
601 Date Built: 6 / 01 / 1971
043066 Order Number: 043066
GA4 Roof Type OR Color: Unknown At This Time
U Built to Specifications for USA Order
A04 Basic (Radio) Group
A36 3.55:1 High Preformence Axle Package
B51 Power Assisted Brakes
C16 Console w/ Buckets
C55 Bucket Seats
G36 Left Hand Remote, Right Hand Manual Outside Mirror
H31 Rear Window Defogger - Blower
H51 Single Air /w Heater
J25 3 Speed Variable Wipers
J45 Hood Tie Down Pins
J54 Sport Hood 70-1
M21 Roof Drip Rail Moldings
N41 Duel Exhaust w/o Tips
N42 Chrome Duel Exhaust Tips
N85 Tachometer
R22 AM w/ 8-Track
R32 Duel Rear Speakers
V9X Black Bumblebee Stripe
26 26 in. Radiator
EN2 End of Codes Assembly Line 2
There are some mistakes with the results (and I don't mean the lousy orthograph).
V9X is NOT a bumblebee stripe in 1971, it is a longitudinal side stripe, black.
Look here to check the codes :
http://www.mymopar.com/6971opcodes.htm
There is only one missing code from all that now, which is the paint code.
Just search Google for 'mopar paint codes GA4' and you will find a few pages that list this color :
GA4 stands for Winchester Grey Metallic (Plymouth name) or Light Gunmetal Metallic (Dodge).