[BigDaveinKY]

One thing I can think of is did you push a wire or drill bit through all the passage holes in the carb?
Best I can remember John Deere used to include proper sized drill bits in their carb rebuild kits to clean the passages.
Also, I had a different brand of tractor that was a 4 cylinder that would do the same thing because of a bad condenser.
Just because you may have replaced a condenser doesn't always mean it's good. I've had more than one condenser bad right off the store shelf. It'll make one pull their hair out looking for another problem.

 

[BigDaveinKY]

You all got it looking good. It didn't look too bad when ya got it ...."cept for the 20 years of dust and tire rot.
I blew up one of your photos and noticed an in-line fuel filter instead of a sediment bowl. Not saying that's your problem, but it could be. A lot of gravity fed tractor fuel systems won't tolerate that type of filter. It won't let enough fuel flow fast enough. That's why a sediment bowl and a very fine screen were used. That's a few things to check. Let us know what you find. Might help another one day.

 

[BigDaveinKY]

Glad you got it fixed. Sometimes we just need a reminder or a nudge in the right direction.