Finally found the problem!
After having it at the dealership where they cleaned the tank and replaced the fuel cutoff solenoid (twice) amoung other things, I was able to track the problem to the controller. 6C190-55510 CONTROLLER(OPC)
To replace it you have to remove the gauge cluster...
My tractor has done this twice now. It starts, runs for about a minute and then dies. Afterward, it won't run. It will crank but won't run. Had been having issues with the fuel cutoff switch (no click on key turn) so I replaced it. Started and ran fine several times after.
I went to use it...