When did GM start using SPIDs and RPOs?

I know the GM started using RPOs like "LT1" and "Z17" back as far as the early 60s, but somewhere between then and now they started using those SPID stickers in the trunk or glove box. I've seen them on GMs as old as 1985, but I can't seem to find one on my 1973. Anyone know when they started using the stickers? On cars before the stickers, is there a way of finding out info like would be contained on the SPID?

I am also curious as to what year they started using the glove box sticker. I think before the stickers your only hope would be to find the "build sheet" which I'm sure you already know about. This is a printout that was used on the assembly line at the factory. They were often stuffed into the car under the seat or other hidden area, but there seemed to be no standard as to were they ended up. Some cars may not have even been delivered with one, since its purpose was only to aid assembly line workers. I have one for my '74 Nova and like the newer sticker it contains codes for the equipment and trim on the vehicle.

I may be wrong, but I believe that they started phasing them in around 84, depending on the production run and such some models didnt get them untill late 80s.

Yo Curtis:

My '84 T/A has one of those stickers under the center console lid..

so they go back as far as 84 or earlier.

My '78 Camaro did not have one- at least when I came into posession of it. I hope this helps narrow down your hunt :)

-BV