Ok I have a 89 mustang 2.3l 4cyl.
Drove it 118 miles round trip got home parked it I while later went to leave it would not crank(solenoid clicks nothing else).I replaced the starter,solenoid and battery still nothing.I tried bypassing solenoid and still nothing.Tried turning key and shifting gears to check neutral switch still nothing.What am I forgetting?

 

Starter relay? Instead of throwing parts at the problem, which is a waste of time and money as you have experienced, try diagnosing it first. Verify that you are getting power to the starter when you turn the key. If not, start back tracking. You probably have a lose/disconnected wire somewhere. The starter and the starter solenoid get ground from the same wire, but they get power from different wires.