Another test to do with your test light is put the alligator clip on battery positive and the probe on the - side of the coil. Crank the engine while watching the light. If it doesn’t flash on and off when the points open and close then the contacts on the points aren’t making up. Depending on what they were cleaned with could cause this because just a tiny bit of sandpaper dust can cause them not to make contact.

Just a thought, check to see it the wire from the coil-to- points is not grounded where it attaches to the points, it happens!
And, sometimes it grounds to the point cover because the gromet is missing where the wire enters the points cover. :bigthink:

UPDATE:
I managed to get the engine to run, and run well last night. Turns out, it [I]was[I] the points. I used Matt Gonitzke's method of static timing and it turn's out the points weren't closing quite enough to contact and charge up the coil, and that's why I didn't have spark. That's the last time I'll be fiddling around with timing. I'll stick to gapping the points at .020 like I did last night; way harder to mess up.
I ran the 149 with the points cover off in case I'd have to make any adjustments, and I was getting a nice, hot spark from them, even with the condenser wired in. The coil is definitely doing it's job this time around! :Kohler1::IH Trusted Hand:

Nice you finally found the culprit and it was a cheap fix.

But timing is still a better method than just gapping the points. Gapping gets you close and gets you by, but timing gets you there.

But I guess either method requires some effort at accuracy.

At last!!
Much easier to have dine this when the engine is out of the tractor and on the bench/stand.
Get it dead nuts right away and be done with it.

One thing I'll try is to vary the gap by .001 at a time and see if that helps at all. It is running very well at the moment, though.

Instead of by gap, you can set your timing by VOM: https://www.onlycubcadets.net/forum/...ead.php?t=4405