Race engine winter storage question

I got the new 20w50 Casttol Classic and Foggit. Ran the car drained the oil,.which looked bad. Kinda a chocolate milk looking mess. Didn't feel very oily. New 51515R filter. I let it warm up. Took a moment more than I liked.to.get oil pressure. Swinging pick up with lots of AN hose to an external filter. Anyway plan on fogging it and pulling the plugs and squirting the stuff in there too. I usually rotate the crank a little through the off season. 600# springs for the solid roller.
And I run water with water wetter during the season. 50/50 green stuff in the long winter sleep. Which brings to mind a question.
What type of coolant do people use with an iron block/aluminum everything else? The mopar 5 year red or the new 10 year or......green stuff. Does it matter? I use green stuff in the aluminum radiator. And before this goes to Evans Cool stuff, well I suppose if it does, I asked for it.