In the shop today I finally got that cluster to shut down after ignition power removed, spent at least 4 hours under microscope and finally found a crack in the solder. Re-flowed and it hasn't failed in 100 attempts. Then repaired the dead PRND321 display, I replaced the stepper motors and bulbs with cool white. This is a GFX special edition and looks particularly nice in cool white with the silver backing.
Don't think I made minimum wage on this one, but the guy will be happy to see it work again. That's all that counts for me. My eyes burn and I will probably have plenty of eye crispies in the morning but I'll survive.