Did a search and didn't see this on here, I just found this myself. Every issue of Popular Science and Popular Mechanics online from Google. Go to books.google.com/ If they don't show up on the page (it is random), go to the advanced search and enter hot rod in the exact phrase box and click full view only and then click magazines select english unless you are multilingual. Here is one: books.google.com/books?id=Qi0DAAAAMBAJ&pg=PA136&dq=%22hot+rod%22&lr=lang_en&as_brr=1&as_pt=MAGAZINES
Wow thats cool. Thanks for the info. On the link you sent, scroll back up to page 60 and look at the Automobiles section in the Business Opportunities.
Somebody posted this a while back. Very cool site. It will take some digging to find the article that you might want. Thanks for throwing this up, I didn't bookmark it last time.