Found my dads original 1971 duster!

Oh hey, dont get me wrong, I wasnt criticizing! You are doing a terrific job of dealing with this colossal undertaking. All I was doing is offering a suggestion as to what would give you the most reliable temp readings to make diagnosing easier for you. Maybe I missed the part about not being able to find a sending unit, why is that giving you grief, is there something different about your intake manifold? My Autometer came with a sending unit that threaded right in, no fuss at all.
I’m wanting to put a proper gauge in it. I’m worried that this whole time my temp gun might be reading wrong or reading metal that’s hotter than the coolant. I dunno. I can understand needing a shroud when idling or in slow traffic, but it seems to get too hot even today, on a 20 minute drive, where air is being forced through the rad at 50-60 mph (I have no traffic where I live)

Next step is me thinking the rad is fucked. I’ve now tried everything else