I have a 1993 F250 460,when I turned key to start there was one click but would'nt turn over.When I turned the key again it started up. Later it took three or four turns of the key to get it to turn over and start.Battery is good.

Make sure that the gas cap is on tight. Some vehicles even have a sticker telling you to turn it so many "clicks" These new vehicles have what is called a closed system.

Sounds like the electrical part of the ignition switch, not the lock cylinder that needs replacing.
Possible also that cutting that wire to the security module immobilized it.

it still sounds like you guys still have a starter problem are you sure you got everything put together right and if so maybe something is worn out inside and not making a good connection

Replace your starter, starting to go bad, sooner or later will not start engine any more, hope this was helpful.

First, make sure you can turn the engine by hand. If you can't then the starter can't turn it either. Have someone else turn the key and look for the source of the click...may be a relay. Go over the starting circuit with a volt meter. Check for power at the starter main terminal and then with the key turned to "start" check for power at the trigger terminal on the starter. Check battery voltage and check relay operation.
You have a neutral safety switch on the transmission if its an automatic and a clutch switch if it's a stick. Check them as well. Make sure battery grounding on fender and block are also clean and secure.

when was the last time u had the timming belt replaced?.....

check you camshaft position sensor 

If the car is dead, it should not make a sound, this is normal for dead things. Get a live one.

sound like a starter solenoid check with a test light . follow your positive battery cable to the solenoid check voltage on both big ternimals has some one turn the ignition to start and it should click and have voltage on both large terms. if you do have voltage on both sides you have a starter problem