There were more than 400 trunk manufacturers from the mid-1800s to the mid 1930's. At least 10% of these manufacturers created as a sideline the making of wooden (and covered) car trunks in addition to their luggage trunks and steamer trunks (which were not that large as a whole). Additionally, other companies making parts for cars had a small line making car trunks. My antique trunk was made by a car spring manufacturer in San Francisco between 1915 and 1930. I know of no book covering just car trunks. But, here is a listing of trunk, car/steamer/other luggage, manufacturers in the USA during the early part of the last century:
http://www.brettunsvillage.com/trunk...unkmakers.html