Would you be willing to fabricate your own dog-house/engine cover? If so you should look at
https://canadianmilitarypattern.com/...20Drawings.htm
Original manuals for the truck do come up for sale every so often. There are also suppliers of reproduction manuals (hard copy) - including me, among others - for the truck. I will send you a PM about these. Research may turn up downloadable or digital (CD, DVD, USB) versions.
Assuming this is for your recently acquired wireless truck, I've never seen a manual for the wireless body though manuals exist for the wireless set and generator.