Cool so that 69 shroud worked in the 67? That's the prior owner - not sure but they were cool mats!Nice wagon. I got a shroud for my 67 300 w/22" radiator from Dante's. Also ordered their bracket kit as noted.
Where did you get the black mats you have underneath your cars?
Were you already based in IL at the time? Ambient weather and humidity can make a big difference. The OP is based in VA and @saforwardlook 's experience in CA (and direct experience with Chrysler engineering) suggests that cooling was in fact borderline on Mopars.I worked in Chrysler garages 69 to '79 and we didn't have any overheating problems with the original equipment. No need to upgrade. I am betting the core is plugged or block is full of rust.
Don't trust aftermarket gauges 100% get a infrared/laser heat gun. Verify that your guages are at least ballpark. Especially the temp gauge. Electric can be affected by car voltage, how good the ground is, and of course gauge quality. Mechanical can be affected by the capillary line running by hot stuff, exhaust, valve cover/along intake with heat crossovers. When air is moving though the engine compartment at road speed not bad, sitting still idling it all gets hot. The alcohol in those boils at fairly low temp which is what makes the pressure gauge read temperature. Of course there is the ever present off shore error in today's products.The prior owner put in Temp and Pressure gauges - helpful upgrade!