Replying to the radiator issue. If you have an 18 lb. radiator cap the boiling point of water/antifreeze is around 150 degrees! Sort of like a pressure cooker. So don’t worry about it unless you start getting around 145 degrees, don’t worry about it. If you don’t believe me, do the calculations yourself.
I’ve added one of the “water wetter” additives which also seems to help plus I added an additional electronic fan too.
I learned the hard way. Don’t release the pressure from the radiator cap until the temperature gets below 205 degrees or it will boil instantly!