I think the jury has returned with a verdict! Great job finding the numbers on the tranny!!! To be they look to match 44DR. That would make it the diesel in a row crop configuration. It is definitely a row-crop but...
It looks to me as though the tub and rear ended numbers are the same. So the only conclusion we can conclude is the engine was once a diesel but at some point in the tractor's life was replaced to the current gas unit.
So what does that mean? In my opinion, not much to most of us!!! If it is a good running straight tractor and you want to put the money into it to restore (or work at cleaning it up) and keep it then it just becomes part of the history of the tractor and can be shared when you sell it in the future. If you are a purest then you would sell it as is and find one that is correct to restore.
The tractor looks good so I would really think about keeping in this condition. Most of the tractor is a 1952 model.
Just my thoughts!