Stopped at Napa and tried to get the #6 thermostat, but not in stock. We limped into Summit Racing in Reno and I was able to get the Robert Shaw #304 160° high flow thermostat. We got the right 3,000 CFM fan to fit our shroud so that can go back on, a stock replacement GMB car water pump and 68 Mustang 5.85" pulley. Tape measure on the parts counter suggests it's the same distance as my truck pump.
Belt width looks the same! Good tip, lots to go wrong here.
We got a motel next to O'Reilly's and I'll swap everything early in the morning when its cool, and hit the road again.
Today was brutal. 300 miles stoping every 5-10 miles to pour water over the radiator to cool it back down. Luckily we never really got hot and over heated, we were able to pull over and get it back under control and rolling again.
Poor Jess was cooking with the heater full blast.