[Kurt S]

There was a decoder in the May/June 94 issue of the USCC magazine. I don't have a scanned copy of it to send you; someone here should.

It's not a bad start, but it's not perfect. I've developed a more accurate decoder. If you send me a copy of your sheet, I can tell you what it says / what options were on the car.
Most boxes reflect what powertrain the car had - a 307 used these components, a Z used these components, etc.