Entirely right about the accuracy point. I would like to think the Japanese resistive temp gauge is accurate but after 25 years how could it be. But the temp dial can’t respond quick enough to a catastrophic scenario to prevent damage. The scan guage is entirely qualitative but it should be able...
I've done more than enough road trips in an 80 to know that the 100 series or a 200 is a better option for long trips. I vote sell the 80. If you're mechanically inclined, fix the 80 before sale. You will recoup the cost of a new block versus selling non-running if you can avoid any labor costs...