2005 western star 4900ex Guages erratic behavior

Hey yall, got an issue that kinda stumped me for a bit... 2005 western star 4900ex lowmax with a detroit60 ddec iv...so troubleshooting some gauge problems and tried some of the methods from other posters with "gauges not working" posts... well heres what i have so far. First, the "a" primary pressure gauge stopped working, then 2 weeks later, "b" res. Pressure gauge stopped working, and is sometimes stuck on 90 psi. Pyro is all over the place now, tranny and diffs gauge bounce around +-50 degrees sometimes. Speedo and tach are fine, trailer emerg. Works fine, tractor application (brake) works fine. And now recently, again, the coolant temp guage spikes to 255 for a second kicking the fan on while driving about every 15 seconds. So WITH THE TRUCK IN KEY ON, NOT RUNNING, the only gauge that bounces around is the water temp gauge and i can hear the air release the fan clutch actuator when it dips below 205. (Again, with the truck off still). Im checking all the wires, and checking the grounds again. I even unplugged that silver box driver side under clutch connecting rods on the firewall and it didnt even phase the gauges. I have years of mechanical experience but these multiplex guages got me stumped!

 

The big silver box behind the guages with the micro pins?

 

This box?

 

Oh ok duh, sorry, been a long workday. Checking now

 

All zeros between the pins