According to this, Worthington used old Ford components. This website has a link to a guy with a Worthington registry, he might be able to help. This link also has a picture of a cute Toro lawn truck, looks like a '40s version of a Gator.
About the only other thing of interest that I found was that Worthington became a part of Jacobsen or Jacobson. I found something that stated that they used Ford drivetrain parts and a Continental engine. Your best bet for info would be to go to www.ytmag.com and post on their Orphans and Oddballs forum.