Shane, you wanted "proof"? Well, here you go -
These seat trim parts (upper and lower) are in the GM parts books FROM BACK THEN under Group 14.818. See these pages from the Chevelle parts book printed in February 1969 --
GMPartsWiki - Parts and Accessories Catalog P&A 34 February 1969
- For 66-67 there are a whole bunch of listings for the lower trim pieces (the left side of a seat referred to as "driver side outer pass side inner", and the right side of a seat referred to as "driver side inner pass side outer". And every single one of them shows a color
. Not one of them is listed without a color, and not one of them says "Chrome".
- Then for the 66-67 seatback trim, there is only one
part listed (p/n 7600026), and it does not mention any color (because it is chrome).
Then see the next page: GMPartsWiki - Parts and Accessories Catalog P&A 34 February 1969
- For 68 there is again one seat back trim part listed (p/n 7737616). Again, because it was chrome.
- But there are NO
seat bottom trims listed EXCEPT
p/n's 4854957-58 which are noted for "Production Deviation Trim Change", for trim combos 765/960, 765/168-980, and 765/158.
If you don't know what those numbers are referring to, those are the 68's that came with BUICK or OLDS or PONTIAC seats! Which DID have lower chrome trim, as everyone has been telling you. And that's why there's only one set of p/n's listed, since those were chrome. (No colors listed because in 68 they didn't put any lower trim on Chevrolet
bucket seats, colored or chrome).
Also look at the listings for the "CAP" (which is the little chrome bullets on the ends of the trim) --
66-67 lists CAP p/n 7584956 as being for "driver and pass. seat side and back
mldg. end". Because 66-67 seats had the trim on the sides and the back, so had to have bullets for all 12 ends of the 6 trim pieces. Note the quantity column says "A.R." (means "as required").
But 68 lists CAP's p/n 7738634-35 as being ONLY for the "seat back
" -- one part number listed for the right side of each seat back, and the other part number for the left side of each seat back (which is something I did not know, that 68's had two different styles of bullets). And note that the quantity column says "2" for each part, so a total of 4 caps for the entire car -- or 2 per seat back. None on the lower sides, because there was no trim there to need a cap.