Here's my issue.
New battery, new starter, new solenoid, and nothing when I turn the key.
Bypassing the solenoid turns the motor over but the starter won't disengage.
Could it be the electronic ignition?

 

So we can be sure of understanding exactly what you are trying to tell us.
Are you saying the engine Does turn over , but doesn't fire up and run or can't start running because the starter won't disengage from the flywheel?

Was your original problem that the vehicle would crank over , but would not start running? If so, the ign system could be involved.
Is this vehicle with a stick shift or automatic?
Or,,,, when you turned the key to the start position you got nothing, no click or anything?

 

My original issue was the engine wouldn't turn over. It's an automatic.

 

And now when I turn the key.....nothing....but all the accessories work.

 

In that case it should have a neutral safety switch. Check that it has power coming to it with the key in the start position and power leaving it on another wire when the key is turned to the start position.

 

one thing you need to do is find out if the solenoid has two little posts on the front or just one. Ford used two different solenoids during this time. and most of the time if the starter stayed engaged then all you would have to do is reverse the two little wires if it has two little posts on the solenoid. one thing that you didn't tell us is whether or not the engine runs or not with the starter still engaged

 

OK....replaced solenoid with an exact replacement......nothing....checked all the wiring to the ignition module and voltage regulator. Walked away and checked again 4 hours later and......turned the key!! Varoom!! Fired right up. Clueless...

 

that sounds like you had some visitors living in it for a little while. or the control box has went bad and you could have some loose connections on some of your components

 

You got to love those magical fixes!

 

Turned out to be a loose ground cable........lol