Same radiator cap so probably same size.
I don't need to remind you how inaccurate the stock gauge is and how a grounded sending wire can send the gauge needle to the hot side. It's really easy to install a real gauge with numbers on it. I happen to think that engine temp is so important that I installed two real engine temp gauges in-dash. Perhaps as important as oil pressure.
It's not easy to overheat an F engine on a quick spin but can be done if you have no coolant, the waterpump is not pumping water or the radiator is clogged. And you've got coolant. A little bubble probably won't matter, remember, these came without coolant recovery bottles and usually had a bubble in them. When did you last have the radiator core rodded out? or re-cored?