Electrical Gremlins? ABS A/C etc

[emmvette]

1990 ZR-1:

Last weekend my ABS light came on and the ABS system went off. Confirmed it on corner #3 of autocross. What's all that smoke under your tires, mister? Oh, that's my ABS not working. It was good to re-learn to brake without the ABS and I was fine. Codes 71 & 76 which are the EBCM and the lateral accelerometer are what I found with the paperclip.

Also had the INFL RES. Light. I fixed that (it was the RF mount) and then reset that code and the ABS codes and took a quick drive. The ABS light came back on and I confirmed it is not functioning.

I removed the tray in the rear hatch and looked around - verified the EBCM is connected.

The night before that happened, I noticed the radio lights wouldn't shut off. I opened and closed the doors (both) a few times and that self corrected - for now.

Then I noticed this weekend the A/C wouldn't work - the whole group of controls does nothing when you touch them.

And I also noticed the little cluster above the A/C controls does not work - the fuel and trip meter buttons. On my digital dash it shows 0 for the fuel mileage and won't change between instantaneous and average anymore. Basically none of the buttons work.

A few times I've also had the selective ride control indicator light come on. Each time it has gone back off within a few seconds or minutes. Personally, I can't tell if the selector works, I can't feel a difference between modes. I understand this isn't uncommon.

Have you guys seen similar issues? Any thoughts on if these are all related? Kind of seems like I may have a ground issue or similar.
I like wrenching, but to be honest I'm not a good electrical troubleshooter.