I've always heard the concensus is that GM can't run your vin number to pull up RPO codes for the older models. Especially the mid 80's.

I was also told this by a GM Dealer in Phoenix...... BUT..... while doing some searches on the board on RPO post of the past I came across an interesting post. It seems at least one member had a friend working in a GM Parts Department who DID pull up his RPO's on the service computer.

I didn't log the post but I did save the picture. This was on a 1984 car. The post was written this year in about January I believe.

Sorry for the billboard size but I wanted you to be able to see.......... wonder what's up with this.

<img src=http://www.gmtips.com/3rd-degree/pix/post/arc/rpos-GM.gif>

I saw this too and wondered about it. I work at a GM dealer and will make a call to Bell & Howell to see what is up with this.
Right now 1990 is as far back as our VIN/RPO will go.