If your company assembles a product that people may want to collect in future decades, consider holding onto old paper work instructions.

I recently came across some old new-car invoices that belonged to my late father. They’re from various car dealerships in Chicago, ranging from the late 1940s to the early 1960s.

Back in the day, Dad usually kept a car for two or three years and then traded it in. Unlike many folks, he wasn’t loyal to any particular nameplate. During a 10-year stretch, Dad owned a variety of Buick, Ford, Oldsmobile, Packard and Pontiac coupes and convertibles.

Most of the dealerships listed on the decades-old invoices are long gone. Also, vanished into history are the price tags! It’s amazing what an Oldsmobile Futuramatic 88 convertible sold for in 1950.

I’m holding onto the invoices for nostalgia reasons. Some day, I hope to frame a few of them along with some old photos of my Dad proudly posing next to his various rides.

Another option would be to sell them. There’s a big market for old car invoices, sales brochures and press materials. Car collectors love to have various types of paper ephemera to go along with the brass, chrome and steel beauties sitting in their garages. There’s also a company out there that markets reproductions of window stickers . . . so that you can recreate a new-car showroom feel.

There’s also a demand for assembly work instructions-if they exist. Unfortunately, many old documents were destroyed long ago. One of the few exceptions is Cadillac. For some reason, the 109-year-old GM brand accumulated a treasure-trove of old “build records.”

Each GM division and plant was responsible for maintaining production information. But, due to space restrictions, most records were destroyed after 10 years. Cadillac is the only GM brand that was able to preserve the majority of its factory build records, dating all the way back to 1903.

The GM Heritage Center recently began marketing the priceless Cadillac paper. It’s charging car collectors $50 to own a piece of history. Actually, it’s a copy that’s printed from microfilm or microfiche.

According to GM, a build record is “a document that followed the vehicle down the assembly line as the car was being built. Assembly line workers used the option codes on the build record to determine which part they were to install. The build record option codes were specific to different vehicle lines and require decoding to understand individual options.”

The documents have taken on many forms over the years. Early build sheets were hand-written in oversized leather-bound journals. More recent records are less personal-they were computer-generated.

Does anyone know if other automakers, such as Chrysler, Daimler, Fiat, Ford, Renault or Toyota, have a work instruction archive?

If your company assembles a product that people may want to collect in future decades, consider holding onto paper work instructions (unless you’ ve already gone paperless, of course). I wonder if old work instructions exist for other mass-produced objects that people collect, such as clocks, pens, typewriters or watches. If so, it’s a nostalgic way for the past to come alive again.