Boot Sticker!!

Just in the last stages of removing the paint from my Elan… and have started on the underside of the boot lid. Now I’m pretty sure it’s had a spray over, however there is residue from a sticker, see image. Would this have been an original if so what? I’ve read a few threads re NEGATIVE EARTH stickers would this be correct or are there other possibilities. It’s a 68’ S4 SE.
Thanks…

My 69 S4 SE did not have a boot lid sticker on the underside.

But there was a negative earth sticker IIRC (red) in the vicinity of the battery (not on the boot lid) that fell off many years ago.

Here is the sticker in the boot.

Thanks for the replies. Judging by the size of the Neg sticker, whatever was on the underside of the boot lid is something different.

None on mine either -early S4 SE