Cloudy Radiator Coolant (After Flushing)

The raw peanut butter can be rust and other crud inside the water jacket. Or is can be old Bars Leak brand stopleak, or oil or trans fluid. If trans fluid, it ought to have a orange or reddish tint. As far as the exhaust smoke, if it is coolant, it will be moist.

I don't recall ever seeing cloudiness in coolant just due to a combustion gas leak into the cooling jacket. I would test the cooling system with a pressure tester if I suspected that; and, if you drive it for a while, that is when it is more likely to overheat.

I am betting you are just still getting the cooling system crud out; I rebuilt our /6 and had the block acid tanked, we flushed and back flushed the rad and heater core, and after 600 miles on the rebuild, the coolant is a murky brown, and needs a fresh change; so we are still cleaning out 40+ years of neglect. I expect you are too.