You will likely find that the hottest cylinder on a 470, or most carburetted engines, is literally a moving target. I had a six channel scanner installed on a carburetted IO-470F back in the late 80's, and found that the leanest cylinder was not always the same one, and varied with power setting. The induction balance tube (across the front of the engine) also had a lot to do with this. There are three sizes, and when we removed the injection, and went carburetted, we had to do a lot of fiddling with this. My current experience with my O-200 with a four cylinder bar graph bears this out. I set power first, then lean to the leanest cylinder.
This is one of the reasons for fuel injection becoming popular, in that the fuel distribution is more precise than carburetted induction systems. Fuel injection systems are not so popular with those who would like to use MOGAS.
So, either install the single cylinder probe, and lean conservatively, or go the extra, and install the six cylinder system (bar graph better). From a CHT point of view, you'll pobably be happy that you installed the six cylinder system as well - interesting indications there too!