The mobile machine shops used during WWII in the back of a truck often included a South Bend Lathe. Did they have a gas powered generator to provide three phase power, or did they somehow transfer power from the truck's engine? I seem to remember that one of our members bought one of these trucks. Gary P. Hansen
There were different variants of the repair trucks for different type of jobs (based on the unit type they would be assigned to). I do not believe that all these had generators but the 'machine shop' style trucks did.
PS there are very active groups of historic military vehicle collectors so if you do a web search you should be able to finds all sorts of details on these trucks.