Sounds like you have a 1957 1-1/2 ton.
The US model would be a 4400, (1-1/2 ton with a 154" wheelbase).
The 283 engine came out in 1957, so unless the engine has been swapped out it would not be a 55 or 56 model.
The 1955 265 is the ONLY SBC engine to use a remote oil filter (optional)...ALL V8's from 1956 on have had the filter cast on the block.
Mike B
