I have a 82 with this paint code:
74I 13L 13U 99M
I'm pretty sure 74I is dark red interior
13L is silver lower
13U is silver upper
I know 99 is dark claret but I can't find any info on what M is for.
Unfortunately the car was painted before I got it so I have no idea what it is supposed to be.
Can anyone help with this?

 

On all '82 two-tones the L & U are the same color & the M designates the lower color.
13/99 would of been Silver upper/Dark Claret lower. My black book shows 74C for dark red cloth...no 74I..

Could it be 742? That's Dark Red leather...

 

I added a pic of the tag. Sorry if it's a bit hard to read. Thanks for the info.

 

I found this note on my favorite code checking site:

"Bowling Green cars may appear with a Leather Trim Code ending in 'l' rather than '2' as shown."

https://corvettec3.ca/interior.htm

 

Build sheets call out the L M and U with M for Middle. I see this often in 78 with the Silver anniversary paint schemes and the Pace Car. L and U were black paint (Pace Cars) and then M called out the lower (called middle) silver paint. Silver was painted in the Impala plant...these were St Louis Plant days while you're 82 is the Bowling Green. The same codes would have applied but one operation at the Bowling Green plant.

I have a wad of 82 build sheets I got from the NCM years ago. I'll look around in the AM and post my findings. Your car was painted in full with Silver (L & U) then the bottom (M) was painted Dark Claret. Hope this helps!

 

The layout of the trim tag changed completely with the beginning of production at Bowling Green in June 1981.

St Louis tags only included interior trim and exterior paint codes, and a month and day assembly date for the body. Bowling Green tags added a VIN derivative, and changed the body build date to include the year and replaced the day date with a week code. The format of the interior and exterior codes was changed, eliminating the words "Trim" and "Paint" from the tag which allowed the tag to include up to four codes for paint and trim. On this new tag the first code was the interior code with the second, third and forth positions for the exterior finish.

The OP's trim tag breaks down as follows:

C - 1982 Model Year (not the year when the car or body was assembled)
04 - Month the body was assembled, "04" is April (1982)
A - The first week of April 82 (second week was B, third C and so on) *
111086 - This is the VIN derivative. 82 VIN 11086 was built on approximately April 13, 1982 *
74I - Is the Interior Color Code, in this case Dark Red **
13U - Is the Paint Code for Silver Metallic ***
13L - Is again the Code for Silver Metallic ***
99M - Dark Metallic Claret Lower accent Paint Code (if the car was a single solid color this area would be blank without the code or an M) ***
E - Enamel Paint

* While the OP's Trim Tag shows the body was built the first week of April and the car's final assembly date is in the second week of April on the 13th, this was actually quite common in 82. It appeared that only whole weeks were considered assembly weeks for dating. The first day of April 1982 was a Thursday so any 82 body assemble April 1st or 2nd would show a build date of "03 E" (March 5th week). The OP's car's body was assembled the first full week of April (April 5-9), and the car was completed on Tuesday April 13th.

** While the Black Book, various websites, and other places indicate the Trim Tag Interior Codes include a "C" for cloth or "2" for leather, I have never found this to be true. As the original owner of a Bowling Green 81 Corvette I spent a considerable amount of time researching the 81 and 82 Bowling Green colors and trim codes while working as part of the team creating the first NCRS 81-82 Judging manual. Every Bowling Green Trim Tag I've seen always has an "I" (not an "L") as part of the interior Trim Code, whether the car had a leather or cloth interior. I don't really know where the "C" and "2" came from, they're not part of the GM ordering guide because it required interiors to be ordered using four digit codes such as "ALL2" (Silver Gray Leather), "HLL2" (Silver Gray Cloth), "ARR2" (Dark Red Leather), "HRR2" (Dark Red Cloth), etc... To my knowledge there is no way to determine leather verse cloth from a Bowling Green Trim Tag.

*** The "U" and "L" Paint Codes were included on all Bowling Green Trim Tags, but only cars ordered with RPO D84 "Custom Two-Tone Paint" included the third "M" Paint Code which identified the Two-Tone Lower Accent Color. If the OP's car was originally solid Silver Metallic with the Dark Red interior the tag would have read 14I 13U 13L and would have ended there without any further numbers or the "M". The primary color on Bowling Green Trim Tags was always repeated twice in the xxU and xxL format, whether it was a solid color or optional Two-Tone. The Trim Tag on my Charcoal Gray Metallic 81 with the Silver Gray (sometimes called Slate Gray) leather interior reads 13I 39U 39L. The Dealer Order Guide is very specific in stating that when a car is ordered with D84 Two Tone the colors have to be ordered as xxU xxL and must include the xxM Accent Color. If the "M" Accent Color wasn't included with the order I assume the order was kicked back to the dealer.

Joe J, welcome to the Forum! How about some pictures of your car and some more information about it. The Forum loves pictures!

 

Awesome info and much more that I'd hoped for. Thanks so much.
One thing I have learned from this is that I hope to never meet the person responsible for the current color of my car. If they had painted it solid dark claret, it would have been fine but they painted the lower black with a not so metallic black that clashes with the dark claret. I have a lot to consider now as to go back factory color or solid dark claret.
I got it about a month ago and have a bit of work left to do finish restoring it but it is drivable. I'll be posting pics as I work on it. Replacing a cracked rear leaf spring this weekend.
Again, thanks.

 

That was an AMAZING reply. I learned some things there! Thank you for sharing!!!

OP:
Silver over Dark Claret Met is one of my favorite color vettes. I think it's THE best 2-tone color. Time to head to Harbor Freight and get a new spray gun!! lol

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