I have a 1952 plymouth cranbrook that I have the paper work from the dealership with the original owner on it,THE ADD HE PUT IN THE PAPER to sell it when it was 6 months old,The check the lady used to buy it off the original owner,the copy of the title and registration from all the owners,(I am number 5) A check stub from every oil change,overhaul,battery,1 engine overhaul,tires,seat covers(from a plymouth dealer),and Under coating that the 2nd owner had done.I even have documentation from a body shop in 1954 that tells me why the bumper is scratched and why there is bondo on the right rear fender.She passed away in the 80s and I have the papers from her power of attorney when the car was sold to the 3rd owner.55,000 original miles but the paint is faded pretty bad.I have about $4000 in it and normally it (being a 52 cranbrook coupe wich is not a real popular car in the hot rod world) would only be worth around $2000 maybe $2500.the big pile of paper work was a big factor for me. So to answer your question,Yes I personally believe that any bit of paper work you have or can find will help in the value of your car.If not now, than maybe in the future. I may have gone over board on a 52 that is not GM but haveing a detailed history of the car is pretty cool. Oh ya I have the original owners manual.