Can I change a 1986 ford f-350 hydraulic clutch to a mechcanical clutch and what parts fit?

Can I change a 1986 ford f-350 hydraulic clutch to a mechcanical clutch and what parts fit?

None. Completely different systems. Even the bellhousing is different. Which means… BIG JOB!

It would be an expensive nightmare.

NO, but there's a service bulletin that was released years ago for firewall movement, cracks, odd wear in the master, connecting the line to the parts, and pedal cross shaft as well as bushings and pedal attachment to the cross shaft.
You could possibly research with Ford parts people, they may even recall there was such a thing. Gas and diesel, especially diesel.