Should have added does the range lever grind if you have the hst pedal depressed and try to move the range lever from neutral to a gear.
It sounds like your clutch is not disengaging.
Reading your first post again the safety switch does not have anything to do with the clutch, you need to adjust the clutch clearances.
To borrow a quote from this website I had directed to me a few years ago, download the workshop manual, you can find many links to it here in the forums.
It will go over the clutch adjustment. Too much and you grind gears, too little and you wear out the clutch.
From your picture, your safety switch is missing. the bolt acts as a stop. the flat bar above the bolt trips the safety switch. Retracting that bolt will will allow the clutch to move further in the disengage direction.
It sounds like that is what is required.
The wire from the key switch to the starter, that is a new one….but since you do not have the safety switch I thought you could just join the two wires from the switch to over ride the switch...
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