I have a 1967 coupe barracuda with a low serial number and shipped march 1966.

Artie, here is one I use from Dodgcharger.org.
It's pretty much foolproof with the spacing.
Surprised the Alaskan show pony hasn't put up a link to help someone out.
DodgeCharger.org -- 1967 Fender Tag Decoder
mymopar.com

Unless I am going blind at which point somebody should stop me!

View attachment 1715437530

CAR: Plymouth Barracuda 2 Door Hardtop
ENGINE: 273cid 2-bbl V8
TRANSMISSION: 3-Speed Automatic
TIRES: Unknown tire code
BUILD DATE: April 24.
AXLE: 3.23 Rear Axle Ratio
INTERIOR: High Trim Grade
PAINT: Monotone Light Blue Metallic Paint.
OTHER: Dark Blue Metallic Upper Door Frame Color.

MOLDINGS:

ABC OPTIONS:
M2: Unknown Option
R1: AM Radio

abc OPTIONS:
u1: Sold Car When Built (Somebody Ordered It)
w6: Build to Spec's for Canada