The oil filter canister was a dealer add-on. There were a few options. Mine was an AC S-2 version (the larger canister) and was mounted on the inner fender on the driver's side. I JUST saw a pic here on Stovebolt of another truck with the bracket like mine has. I'll see if I can track that down again. Before today, I hadn't seen the mounting bracket like mine. Some were mounted to the intake manifold in front of the carb.
There's a
Tech Tip on the different variations of add-on oil filters.
[on edit] Can't find that picture again. But a pic of my oil filter and bracket is attached.