Practically by definition, hot rods are prone to overheating. (After all, they’re not lukewarm rods, right?) Of course, to prevent the occasional boil-over, you can do the obvious, such as turn on the heater (to dissipate heat from the block) or drive at a slower speed (unacceptable). You also can put straight water in the radiator (which is actually more efficient for heat transfer than a 50/50 mix of coolant and water), or you might find that using synthetic oil or other super-slick lubrication might lower your gauge a few degrees.
If none of these quick fixes do the trick, and a pegged temp gauge is a more persistent problem, you may need to make a few changes. That’s exactly what So-Cal Speed Shop did on a 1933 Ford coupe powered by a 454 Chevy. The owner was getting really steamed up about overcooking his coupe, so he asked for some simple alterations. One was to swap out the thermostat for a 160-degree unit that opens at a lower temperature level. A water-wetting agent may improve heat exchange as well. For this particular Chevy engine, air bleeds at the rear corners of the intake manifold helped to remove trapped air and increase water flow. Your own Old Faithful may not require all of the following to keep from spewing steam, so try one at a time to see what works (the pulley swap proved to be the most effective on this particular rod). The only thing you have to lose is some hot air.