S650G serial number lookup?

[PHPaul]

Just acquired a S650G as part of a barter deal. Not running, wiring harness is a disaster, missing the distributor.

Engine is loose and tractor is otherwise in decent condition, so I'm going to try to get it running. Couple of questions:

1. Is there a serial number list that I can cross to a year? Serial number on trans case is S650G-800732

2. There were apparently 2 different Mazda engines used. I'm assuming I have the smaller one but need to confirm that. All I have is what appears to be a serial number. It's on a machined boss under the exhaust manifold. S296869

3. Any leads for parts sources appreciated.

 

[Sonny580]

They told me that the engine in mine was the one used in the 626 sedan car----- thats all I know about the engines--I assumed there was only 1 size, but could be wrong.