Most of the info is in the Library. Look in General info and then scroll down to 1.14.
https://h-body.org/library/hbodyfaq/index.html1.15 How do I decode the trim tag on my H-body?
There are two styles based on the plant. However, Brian Melka (Bacchus_101573) notes that his '75 Canadian-built car has a tag like that shown below for the Ohio cars. So, check both...
Lordstown, OH plant (Vegas 1971-1977, Monzas 1978-up)
Examine this sample tag (found on or near firewall on most cars):
______________________________________
/ \
| ST 78 1HR07 U 344361 BDY |
| TR 19V A51 77L 77U PNT |
| 05B 19X 69-3681 |
| 191601 02BLK |
\______________________________________/
Top line, left to right:
* ST = printed on all tags, probably means "style"
* 78 = Year of production
* 1HR07 = Make, carline series, and bodystyle (see VIN decoding)
* U = Assembly plant (see VIN decoding)
* 344361 = Production Sequence
* BODY = printed on all tags
Second line, left to right:
* TR = printed on all tags, probably means "trim"
* 19V = Trim Combination Number (see option codes)
* A51 = Modular Seat Code (see option codes)
* 77L = Lower Body Color (see option codes)
* 77U = Upper Body or Fabric Top Color (see option codes)
* PAINT = printed on all tags
Third line, left to right:
* 05B = Time Built Code--produced in week B (second week) of month 05 (May)
* 19X = Option Designation for plant use; probably means Black carpet
(see option codes for more)
* 69-3681 = Option Designation for plant use; 69th day of production
for this model year (or possibly 169th or 269th) + a scheduling number of 3681
Fourth line, left to right:
* 191601 = Option Designation for plant use; 91,601st car for that
model and model year
* 02BLK = Option Designation for plant use; option code Z02
(Spyder appearance package) in Black ???
Ste. Therese, Quebec plant (Monzas 1975-1977)
Examine this sample tag (found on or near firewall on most cars):
_______________
/ \
| 01C 106 449 |
| 1HR07 025393 |
| 11L 11U 71V |
\_______________/
Top line, left to right:
* 01C = Time Built Code--produced in week C (third week) of month 01 (Jan)
* 106 = Day of production for this model year
* 449 = Option Designation for plant use (???)
Second line, left to right:
* 1HR07 = Make, carline series, and bodystyle (see VIN decoding)
* 025393 = Production Sequence
Third line, left to right:
* 11L = Lower Body Color (see option codes)
* 11U = Upper Body or Fabric Top Color (see option codes)
* 71V = Trim Combination Number (see option codes)