1991 Ford F-150 shorts out when inition key turned on

When I turn my ignition key to start my truck, the lights on the dash go out and I heard a click for the solenoid but it doesn't crack. Playing with the key [turning it on and off] resets the dash lights but when I turn it to crank position, it shorts out again.

I have power windows and door locks. When I turn the key for power to use those items, theres not enough power from my battery to make even the door locks work.

I have replaced recently, the battery, alternator, solenoid. I do have a by-pass toggle switch that I need to flick under the dash in order to start my truck connected to the solenoid.

My truck started having this problem about a week ago but playing with the ignition key or taking the shifter out of park and back into it fixed the problem so I could start it. Didn't do it for a whole week.

What part is faulty or where should I begin to look for the electrical short?