I took my multi meter and checked the coil. Still not sure if it is good or not. It was no where near 4500, it was 5 point something but I think it meant 5000. Check out my pic and tell me what you thinkYou can do a quick check of the coil with an ohmmeter. Between the metal magneto case and the spark plug wire or wire socket you should read 4500 to 6500 ohms. That is checking the secondary windings of the coil; if you get a higher reading or no reading, remove the front cover and try again right at the contact button on the coil.
If you still have no reading or an open, then the coil is bad. If the reading is below 4500 ohms, then some of the windings may have shorted out to each other.
If your tractor has the stop button in the right handle bar, remove the stop wire from the magneto post and try again, the wiring for the stop switch shorts out some times.
If the coil checks, and you cleaned and set the points, try replacing the condenser, Richards or Todd White can help you out.
I just looked at your photos again of the tractor, yes do get another spark plug wire and make sure that it has a wire core, not carbon.
We see the yellow color, does it have any Postal numbering? The U.S. Post Office used a lot of yellow Gravelys.
No question about it.I do believe this machine will run with a little work