Here are your parts
Parts for Whirlpool GR563LXSB1 Range - AppliancePartsPros.com

See the attachment for the tech sheet.

I am assuming that the unit stays in preheat (never comes ready).

Sounds like the control board is shot.

It would not hurt to check the following:
the wiring to/from the control board for the elements and terminal strip.

The oven elements. But would be very very rara that they both go out at the same time.

The thermal fuse. But it only effects the broil element.

[COLOR="Blue"]Now I'm afraid to order a control panel and it turn out to be a wire harness issue which I don't know to test. [/COLOR]
Yes bad connection problems can be a pain to troubleshoot.
As soon as you move anything which you are forced to do with this unit it can start working again so troubleshooting is very difficult.
I can give you a couple tips on what to look for.
Check for discolored connectors. Sometimes they can get a discoloration and just need cleaning up. Use isopropyl alcohol or electronics contact cleaner.
Check for poor crimps at the connectors.
Check that the connectors are seated correctly in the plugs. Sometimes the liitl clip ogn the connector can come loose from the plastic body and the metal connector can back out when you try to plug the connector in.

I am not sure what you moved so it started working but I would check the solder side of the control board for bad solder joints.
Bad solder joints are often a duller silver color and/or may have pin holes.
Also while looking at the solder side or the board gently wiggle the part/connector to see if it's leg moves in the solder.
A magnifying glass helps here.


[COLOR="Blue"]Thinking that after calling a service repair man and buying a harness or control panel ... maybe I should just buy a new stove...what's your opinion?[/COLOR]
Unless you can find the actual fault location it is a gamble.
Who knows the think might never again have a problem.
I cannot really advise on whether to replace the unit. a lot depends on how much hassle you are willing to put up with if this is a true intermittent problem.