An honest reference, built to be checked.

The RPO Archive is a reference to General Motors Regular Production Option (RPO) codes for classic-era GM vehicles — model years 1960–1982, six divisions, 26 model pages, 4,387 option rows.

Every other RPO list on the web copies from the same handful of sources, inheriting their errors and offering no way to tell a solid entry from a guess. This one is different in one specific way: every code carries a confidence grade, and where a factory document confirms it, a citation to the exact GM Heritage kit and page. That evidence is shown on the code, on the vehicle, and here — never merely asserted.

How it was built → — the parallel research, the adversarial source-checking, and the OCR of 282 factory kits behind the reference.

How to read a code

Four grades, shown as a glyph and a label so they never depend on color alone:

• ✓ Factory-verified — confirmed and backed by a GM Heritage factory citation. The strongest grade.
• ● Confirmed — corroborated by multiple independent sources, without a factory citation.
• ◑ Single-source — documented in one source only. Provisional.
• ⚠ Disputed — sources conflict. Both readings are shown; we never silently pick one.

What this is not

There is no VIN decoding here — that is DecodeThis, which we link to from every vehicle page. There are no accounts, no comments, and no tracking. The site is fully static, generated from a curated, rigorously sourced dataset that is versioned and graded. This website is how that data is published and accessed.

Trademark & independence

This is an independent reference work. It is not affiliated with, sponsored by, or endorsed by General Motors. “GM,” “Chevrolet,” “Pontiac,” “Oldsmobile,” “Buick,” “Cadillac,” and “GMC” are trademarks of their respective owners, used here nominatively — only to identify the vehicles the data describes. No GM logos, emblems, or script badges are reproduced. Naming the source of our accuracy honestly is part of what makes the reference trustworthy.