1978 trim tag, whats the L after 13 mean?

 

...it stands for "LOWER".

 

In the Black book L means Leather.

 

Wow, leather paint. That black book impresses me more and more every day.

As Paul said, L is for Lower. GM standardized the paint coding system across all cars lines. U was for upper, so two tone cars had two paint codes.

 

On my trim I have "L" too after number 19.

I have a black '81

 

Haha- my bad, only on my first cup of coffee. I did not see any info re "L" or "U" in the black book, only a reference for upper surface and lower surface paint color, didn't make the connection and misread the tag.
Sorry.

 

This is correct, except Chevrolet didn't use the "L" for 78 Corvettes with two-tone paint jobs. The "L" & "U" did not appear together on any trim tags for Corvettes built at St. Louis.

78 Pace Cars and Silver Anniversary's are marked 19U 47M (black over silver) and 13U 07M (silver over charcoal) respectively. I don't believe that GM considered these cars as true two-tones, but instead called the lower color an accent color, and marked them with the "M".

Starting with Bowling Green production in June 81, ALL BG Corvette trim tags had a paint code with an "L" and a "U". Bowling Green cars have the primary paint color code repeated twice, next to both the "L" and "U". A BG car painted solid charcoal gray has a trim tag coded 39L 39U, 39 being the charcoal code. An 81 two-tone silver over charcoal is marked 33L 33U 39M on the trim tag. 33L and 33U being the silver primary color of the car and 39M being the charcoal lower accent color. An 82 silver over charcoal would be coded the same way, except that silver was changed from 33 to 13 in 82, so the tag would read 13L 13U 39M.

GM adopted the "L" & "M" usage in 1975. Prior to 75, all Corvette paint codes were 3 digit, and started with a "9". For 75, the 9 was dropped, creating a 2 digit paint code for ordering. The "L" was then added to the end of the 2 digits on the actual trim tag.

 

Ok, thanks for for the help, I was begining to think i had a trim tag typo. So it didnt have factory 2 tone paint, It will when I am finished, Im also changing interior to oyster.