Serial Numbers from A C

Is there a source of finding the serial number of a tractor that was sold new to a customer in the 1960's-70's, maybe some old company records that have been archived somewhere? I know that the dealerships would have record of serial numbers but would the company have the serial number and customers name of new Allis Chalmers equipment purchased.

I am trying to track down an Allis tractor that my grandpa bought new and I think that I may have found it based on stories of it changing hands. The dealership he bought it at has been closed for years.   A former employee there told me he thought their records may have been burnt. We have a picture of the tractor, and it matches the tractor I have found but can't tell for sure without the serial number. If anyone could give me some advice or point me in the right direction I would appreciate it.

However there is a story of two brothers from Alabama that will find you any serial numbered tractor that you desire. They will even sell you a tractor with a serial number lower than what the factory produced.   Only problem they don't know up from down!

This is what I think, believe it or not. When the tractor was sold new, there would have been a record of it from the selling Dealership. The Dealerships information would have been sent to the Branch Warehouse. Then, the Branch Warehouse sent it to Milwaukee .  After the warranty period was up, Milwaukee could have cared less about that tractor. How many times did some tractors get traded off for a different model??   More that way than actually stay with the original owner I'd guess.  Every time a tractor was traded in and resold, Milwaukee never knew about it. Why would they ??