Well it was my own stupid fault. When I got my truck it was missing the sheet metal filler piece between the bottom grille bar and the radiator, so the air flow through the grille was not all forced into the radiator. After I blew up the 350 I discovered this problem, was able to source a take-off bottom grille pan, and have been running cool ever since with my Stovebolt 6s.
Best of luck with your project! Sounds like your truck is going to be a very sweet ride. :-)
