Cletrac year and model

[Kirk-NJ]

My friends father just gave me a cletrac. It has been laying in the woods for 20 years. The engine is a hercules. The plate on the engine said
Engine 240622
size 4X4 1/2
Model OOC
 It is a 4cylinder gas engine. Magneto and hand crank. The engine is stuck but was driven into the woods 20 yrs ago. (Ran when parked). I am a new menber and don't know how to post a photo.
Any idea what model and year it might be so I can get a manual for it? I didn'd see any other plates but maybe I'm looking in the wrong spot.
Kirk

[John Schwiebert]

I would say it is either a model E  or an A as it does not have the gas tank on the outside. I will look tomorrow. The OOC engine was dropped durrring World War 2 because those engines were used for the war effort. 1942 or 43 )was the last year for the model A four cylinder crawlers. When production resumed it was with a 6 cylinder Continental F-226 and it became the AG-6 model. Model E production was dropped at this time as well because plant space was necessary for war production. I need to check my records but I think 1937 give or take a year was the first year of the streamlined models. I will do a little looking but it may be Tuesday.