1968 Barracuda. Is this the stock radiator?

I am going off of the stock gauge. How accurate that gauge is is a good question. It gets all the way up to the final bar before the "H", and that's on the interstate on a 40 degree day. I do not know if the carb is tuned correctly, or if the thermostat is working properly. I just had the radiator flushed so it probably needs topped off too. These are things on my TTD list.

running hot can come from a lot of things - be sure your thermostat is opening fully (replacing it might be top of my list) Looks like a decent radiator - you really don't want stock unless your out to build a numbers matching a garage queen - they were undersized IMO- I got a new aluminum 22" 4 -strand that keeps my '68 383 very cool in all driving conditions. btw I added separate new gauge cluster - old ones not reliable IMO. fwiw