The service manual booklet (where the dealer/indy shop would "stamp" the book and mark the mileage where various maintenance tasks were accomplished) as part of the owner's manual pack, had a stapled-in page with a plethora of mileage stickers at various mileages (IIRC 7,500, 15,000 and 30,000 mile intervals).
When a lubrication or maintenance service was performed, the technician or service manager would remove the next interval sticker and place it in the driver's door jamb as a reminder to the owner/operator as to when the next time to bring the car in for service was.
These can be removed with no problem, or if you have the owner's manuals you can bring it up to the current/next service interval as a reminder to yourself.
Cheers,
Gerry
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