Do you have ANY information from those decals?
Do you have a build sheet for your car?
Do you have a SPID sticker in the trunk?
I did these for someone with an 86 SS. Note the RPO B5T.
They had a worn out door jamb decals and SPID still on the car, so that information is valid. VIN altered to protect the owner. Made a window sticker for him too since he never had one, but didn't have a number for him. (somewhere in the 160s was the guess)