This truck is More, the Penhold M211 which came in a 3 truck deal along with 2 parts trucks, M135's called Larry and Curly.
We think we solved the "Attach Stuck White Knight Here" stenciled on the back with the possibility that this truck pulled the "White Knight" ambulance out of the mud....maybe.
This one also came with tailgate and tie-down mods. Being a civilian has its disadvantages so I've never seen what was on the back but it was clearly modified to carry something. Still hunting for pictures of duties the M211 had while it was in service.
I've spent some time checking out images of "Canadian WW11 junkyards", "Canadian WW11 dumps", "Canadian WW11 wreckers"....and so on. Finding a Diamond T with a gun ring is a tough find. There is one near the bottom of this page but not sure it's the right model.
http://usautoindustryworldwartwo.com/diamondt.htm
Here is More, the M211.