When you turn the key on, do you hear the fuel pump running? You should hear a hum and clicking sound from under the seat.
If not, check the fuses. Unplug the fuel pump, and test the wires for power, and ground, with the key on.
If the pump has power, try hitting it with a hammer, and see if it runs. If that, happens you need a pump.
If the pump was running, replace the fuel filter, and test it again.
You can also try removing the fuel line, and see if fuel flows from it via gravity. A small obstruction in the tank could cause an issue there.
There is a relay for the fuel pump, under the dash, that may have failed, I would pull it and check for corrosion, and power.
There have been some ignition switch failures, I don't think you can rule that possibility completely out here.
I suggest you post future questions pertaining to your GC, in the Massey Ferguson Owning and Operating forum. People who actually own them, are much more likely to see it there. You will probably get help faster.