Starter issue Options

[6GCSLED]

So I thought I had a bad starter but it seems it is something else. Put a new one in and it ran for the night and then wouldn't start. Took it back out and to AutoZone, and they tested it and it's fine. Put new starter relay in, still nothing.

New battery, new alternator, everything is charged and gets full power. I'm lost.

[Box]

Grounds, power wire to the starter, battery terminal connectors. How are all of those? Corrosion could be your problem, especially living in an area that uses salt on the road.

[6GCSLED]

Grounds, power wire to the starter, battery terminal connectors. How are all of those? Corrosion could be your problem, especially living in an area that uses salt on the road.

Grounds are.... OK? not really sure how to actually check them besides by eye.

Power wire to starter, from battery, I bought a new connector with dual leads from the terminal, one for the starter and one for the actually harness 12V.

Terminal, see above, new.

And corrosion is a possibility, but where exactly?

Is there a way to bypass all wiring from the key to the actual starter?

[Box]

With a multi-meter, check for continuity and resistance. If where the grounds go to the body are rusty clean them off, any connectors for wiring if they're corroded clean them off. Now when it's not starting is the starter still spinning or is it nothing at all? If nothing at all could be ignition switch, if it still spins over could be the ignition coil. One of those things where you just have to go through and diagnose everything until you find the culprit.

[6GCSLED]

Nothing at all.

I'm guessing the ignition switch, because nothing is happening as well, but I don't know how to access that. I have the cluster out and the key cylinder removed, i can't see the switch, then again, I don't know exactly what I am looking for. Or how to repair/remove/replace it.

[6GCSLED]

So I just ordered an ignition switch just in case, is there an easy way to replace it?