Questions: Fluids and Wiring

I like the genuine Mopar long life coolant (yellow), have had these engines apart I modern Mopars after many miles and no sign of any corrosion, expensive stuff out here in Aussie, but well worth it where you have a mix of metals.

Any good quality full synthetic 0W-40 oil should be fine, or you can use 5W-40 in hotter climates. The 6.1 doesn't have MDS, so should less sensitive to oil viscosity than the 5.7.