What model is my tractor?

I recently bought a small farm tractor at an
auction from a local farm equipment repair/sales/autioneering-type business.
The body of the tractor has been repainted, apparently a number of times, and there are certainly no remaining decals or name plates that I could find on it. The auctioneer stated that it is a Deutz-Allis tractor, though I noticed that the key ring had "Allis-Chalmers" written on it in magic marker. I have since figured out that the two companies are apparently related,
and I"m not necessarily concerned about that distinction so long as I can figure out a model number and get a shop manual for it. When I went back to pick it up, I asked several employees of the business and even one of the owners/auctioneers what the model number/name was, but they all swore that they had absolutely no idea whatsoever. (By that time, of course, I"d already paid for it.)

I assumed I might be able to figure out the model by means of the Internet, but it is not as easy as it would seem. Most sites assume I already know the model number, and few offer pictures of what the models actually look like or any way to search by characteristics rather than model number.

Can anyone help me out? The tractor is a diesel,
with 4-wheel drive. When I say it is a small farm tractor, I mean it is roughly the size of an old Ford 8N. The rear tires are only waist high and the front tires are knee-high. It came with a loader that appears to have been made for it.

If anyone can help me figure out what I have, I"d really appreciate it.

Metheglin Hill of Berkshire, NY

If so, it"s the 5020 that"s being described. This is the same tractor, "badged" as a Simplicity.

I wonder how the sales people knew it was Allis Chalmers if they had no idea of the model number. Maybe they identiifed by the color of paint. Can you tell if any of the paint is green? In that case, it might be a Deutich Allis which I have very little info. In fact, it may not even be Allis Chalmers. Reply to my email and I'll send you these pictures.

And you could take a picture and send it to me.