I do not think you have a Ford F53.
What you have is a 1988 John Deere Chassis W/460 V-8 Ford engine.
Then Gulf Stream built a home on it.
Here is what you are talking about
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The hex nut should unscrew and the cable should then come out with the driven gear.
The drive gear alignment is held in place on the shaft with a ball in the output shaft. The drive gear is also held in place on the shaft with a snap-ring.
You may have lost your ball if the drive gear melted.
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