67 Dog dish caps

[gms]

I recently purchased a set of 3890679 poverty caps. Bought them as an NOS set. They have the GM part number written in marker on inside, they were not in gm boxes. Does anyone know if this was standard practice or give any advice on how to differentiate original from reproductions. 

[169INDY]

I would Argue that Handwritten would NOT have been a Standard for Part identification specified by GM.
Consider the Wide usage of: Ink Stamping, Cast Letter and Numerals, Corp. Stickers, Metal deformation stamping, Foil Decals, Rolled Stamps, Etc.
Also Most Alum and Stainless trim have NO ID in many cases, Think When the Automobile Part is Decorative Ornamental the ID was then specified to be on the outer container and Not on the actual Part such as the ID would detract or diminish the quality of the part or be detrimental to fit and finish.

Just my random thoughts.

Jim

[boomer632]

I know its not 67, but FWIW heres a photo of a stamp on one of my DD cap on my 69 for reference. Ive seen that marking before on 68 DD as well. Ive heard that back in the day, GM sourced the DD caps from a manufacturer in Canada.

The reporos are made of much thinner metal when I compared to a known original.

[gms]

Thanks guys for the info.  I compared the caps to some 30 yr old caps. Turns out one of them had part # written inside. Checked the weight and there were only 1-2 grams difference.
I believe these are original GM counter parts.
Cap on right is purchased cap.

[KurtS]

The supplier plant would not write the part # on the part like that. Looks like they got separated from their boxes and the dealer / vendor wrote the part # on them.