sorry, I've got no info on that one

If you google "b807 yale service manual" you can find PDF manuals for sale, some from questionable sources but they are safe to use via PayPal

Also, you'll sometimes find paper manuals on eBay. The yale parts manuals used to have schematics as well but I haven't seen that in the newer models. If you're going to be working on the truck in the future manuals would be a good investment. Sorry I couldn't help.