Latest development: Started car up to warm it up and check timing and do some troubleshooting based on suggestions in this post.Barely after warm up period radiator started spewing antifreeze out the filler neck with or without cap. Not overheating though as filler neck was around 170 degrees. Thermostat housing surface temperature reading around 246 degrees. Trying to figure out the big delta between housing and radiator. Infrared meter has adjustable emissivity feature so I can calibrate to type of surface I am reading. Sounds like bad thermostat which I will need to replace before I cam follow up on other suggestions.