Bii4x4

So I have had issues with my 4x4 for quite some time. And I generally have been ignoring it, but it's time to get it fixed. I've seen a lot of posts about the 4x4 and most seems to point to the switch, but I think my switch is good. It has lights on, and when I choose a different option than 2wd it will flash and keep flashing. I hear a clunk which I believe is the transfer case actuator working, but 4wd does not actually engage. If I set it to 4lo, it will go into 4lo, and the speed vs engine rpm is right, but it only flashes and the front wheels are not engaged.

Now I've had all kinds of electrical gremlins in this truck. The AC blower motor is on a switch because the mode by it keeps burning up, I have the interior thermal fuse for the passenger side windows pulled because there is a short somewhere in it, and the RVC likes to keep it running up at 15 volts all the time regardless of battery charge level, and one of the daytime driving light bulb connectors is burnt and now disconnected.

I'm thinking there is something with a ground wire causing the 4wd issues, but not sure where/what to start with.